diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow/gapic_version.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow/gapic_version.py
index 9b865da49b92..558c8aab67c5 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow/gapic_version.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow/gapic_version.py
@@ -13,4 +13,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-__version__ = "2.34.0"  # {x-release-please-version}
+__version__ = "0.0.0"  # {x-release-please-version}
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/gapic_version.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/gapic_version.py
index 9b865da49b92..558c8aab67c5 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/gapic_version.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/gapic_version.py
@@ -13,4 +13,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-__version__ = "2.34.0"  # {x-release-please-version}
+__version__ = "0.0.0"  # {x-release-please-version}
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/agents/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/agents/client.py
index e268a6448af7..d7c32d2724b4 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/agents/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/agents/client.py
@@ -461,36 +461,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = AgentsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -500,13 +470,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or AgentsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/answer_records/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/answer_records/client.py
index 464cf1e483ae..a46c15f776e1 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/answer_records/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/answer_records/client.py
@@ -502,36 +502,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = AnswerRecordsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -541,13 +511,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or AnswerRecordsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/contexts/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/contexts/client.py
index 812cb58b9027..23588a58a03a 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/contexts/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/contexts/client.py
@@ -465,36 +465,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = ContextsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -504,13 +474,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or ContextsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_datasets/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_datasets/client.py
index 164733bc1b43..dcf6ae69a923 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_datasets/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_datasets/client.py
@@ -475,36 +475,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = ConversationDatasetsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -514,13 +484,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or ConversationDatasetsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_models/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_models/client.py
index 54f1c39f76f0..dcc671d4c569 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_models/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_models/client.py
@@ -537,36 +537,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = ConversationModelsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -576,13 +546,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or ConversationModelsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_profiles/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_profiles/client.py
index bc9f2b8b8755..1709d82f8e98 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_profiles/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversation_profiles/client.py
@@ -595,36 +595,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = ConversationProfilesClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -634,13 +604,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or ConversationProfilesClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversations/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversations/client.py
index 99e6ea93254b..f0a25fcc4950 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversations/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/conversations/client.py
@@ -649,36 +649,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = ConversationsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -688,13 +658,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or ConversationsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/documents/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/documents/client.py
index 209e6a606148..dd134e33c832 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/documents/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/documents/client.py
@@ -469,36 +469,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = DocumentsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -508,13 +478,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or DocumentsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/encryption_spec_service/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/encryption_spec_service/client.py
index 1c232c38b644..d6ffafae5a17 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/encryption_spec_service/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/encryption_spec_service/client.py
@@ -468,36 +468,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = EncryptionSpecServiceClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -507,13 +477,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or EncryptionSpecServiceClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/entity_types/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/entity_types/client.py
index 7b13a6e8ffc7..c807dec85452 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/entity_types/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/entity_types/client.py
@@ -466,36 +466,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = EntityTypesClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -505,13 +475,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or EntityTypesClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/environments/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/environments/client.py
index e261f45ccbc6..1f41de4307e8 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/environments/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/environments/client.py
@@ -496,36 +496,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = EnvironmentsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -535,13 +505,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or EnvironmentsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/fulfillments/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/fulfillments/client.py
index b72fc87612d8..c35606a4b198 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/fulfillments/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/fulfillments/client.py
@@ -458,36 +458,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = FulfillmentsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -497,13 +467,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or FulfillmentsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/generators/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/generators/client.py
index 4cbacf73ec62..e7fbd3e6d3f1 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/generators/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/generators/client.py
@@ -470,36 +470,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = GeneratorsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -509,13 +479,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or GeneratorsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/intents/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/intents/client.py
index e829ac8d6fea..84b6a43efd15 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/intents/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/intents/client.py
@@ -486,36 +486,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = IntentsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -525,13 +495,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or IntentsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/knowledge_bases/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/knowledge_bases/client.py
index 42937d5d99c4..aa84ff448b5f 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/knowledge_bases/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/knowledge_bases/client.py
@@ -465,36 +465,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = KnowledgeBasesClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -504,13 +474,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or KnowledgeBasesClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/participants/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/participants/client.py
index b7d69271c341..f30b5b9ecf7b 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/participants/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/participants/client.py
@@ -573,36 +573,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = ParticipantsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -612,13 +582,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or ParticipantsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/session_entity_types/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/session_entity_types/client.py
index 8d565a51c952..cc46abe22863 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/session_entity_types/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/session_entity_types/client.py
@@ -471,36 +471,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = SessionEntityTypesClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -510,13 +480,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or SessionEntityTypesClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/sessions/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/sessions/client.py
index 35d5a4dcedcc..62fa8ea17c5f 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/sessions/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/sessions/client.py
@@ -528,36 +528,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = SessionsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -567,13 +537,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or SessionsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/versions/client.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/versions/client.py
index 90c8579ada56..b61fa2c04bc0 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/versions/client.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2/services/versions/client.py
@@ -462,36 +462,6 @@ def _get_universe_domain(
             raise ValueError("Universe Domain cannot be an empty string.")
         return universe_domain
 
-    @staticmethod
-    def _compare_universes(
-        client_universe: str, credentials: ga_credentials.Credentials
-    ) -> bool:
-        """Returns True iff the universe domains used by the client and credentials match.
-
-        Args:
-            client_universe (str): The universe domain configured via the client options.
-            credentials (ga_credentials.Credentials): The credentials being used in the client.
-
-        Returns:
-            bool: True iff client_universe matches the universe in credentials.
-
-        Raises:
-            ValueError: when client_universe does not match the universe in credentials.
-        """
-
-        default_universe = VersionsClient._DEFAULT_UNIVERSE
-        credentials_universe = getattr(credentials, "universe_domain", default_universe)
-
-        if client_universe != credentials_universe:
-            raise ValueError(
-                "The configured universe domain "
-                f"({client_universe}) does not match the universe domain "
-                f"found in the credentials ({credentials_universe}). "
-                "If you haven't configured the universe domain explicitly, "
-                f"`{default_universe}` is the default."
-            )
-        return True
-
     def _validate_universe_domain(self):
         """Validates client's and credentials' universe domains are consistent.
 
@@ -501,13 +471,9 @@ def _validate_universe_domain(self):
         Raises:
             ValueError: If the configured universe domain is not valid.
         """
-        self._is_universe_domain_valid = (
-            self._is_universe_domain_valid
-            or VersionsClient._compare_universes(
-                self.universe_domain, self.transport._credentials
-            )
-        )
-        return self._is_universe_domain_valid
+
+        # NOTE (b/349488459): universe validation is disabled until further notice.
+        return True
 
     @property
     def api_endpoint(self):
diff --git a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2beta1/gapic_version.py b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2beta1/gapic_version.py
index 9b865da49b92..558c8aab67c5 100644
--- a/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2beta1/gapic_version.py
+++ b/packages/google-cloud-dialogflow/google/cloud/dialogflow_v2beta1/gapic_version.py
@@ -13,4 +13,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-__version__ = "2.34.0"  # {x-release-please-version}
+__version__ = "0.0.0"  # {x-release-please-version}
diff --git a/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2.json b/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2.json
index 084e1b53ff18..dde14d384e60 100644
--- a/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2.json
+++ b/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2.json
@@ -8,7 +8,7 @@
     ],
     "language": "PYTHON",
     "name": "google-cloud-dialogflow",
-    "version": "2.34.0"
+    "version": "0.1.0"
   },
   "snippets": [
     {
diff --git a/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2beta1.json b/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2beta1.json
index 563223cb69b5..58a96bc185e8 100644
--- a/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2beta1.json
+++ b/packages/google-cloud-dialogflow/samples/generated_samples/snippet_metadata_google.cloud.dialogflow.v2beta1.json
@@ -8,7 +8,7 @@
     ],
     "language": "PYTHON",
     "name": "google-cloud-dialogflow",
-    "version": "2.34.0"
+    "version": "0.1.0"
   },
   "snippets": [
     {
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_agents.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_agents.py
index 70ad85ba9137..b31827b8bd22 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_agents.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_agents.py
@@ -298,86 +298,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (AgentsClient, transports.AgentsGrpcTransport, "grpc"),
-        (AgentsClient, transports.AgentsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_answer_records.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_answer_records.py
index e0e04b61e4dd..1f44e1447d4f 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_answer_records.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_answer_records.py
@@ -321,86 +321,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (AnswerRecordsClient, transports.AnswerRecordsGrpcTransport, "grpc"),
-        (AnswerRecordsClient, transports.AnswerRecordsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_contexts.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_contexts.py
index 2126f528242f..feff4fc95e5e 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_contexts.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_contexts.py
@@ -295,86 +295,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (ContextsClient, transports.ContextsGrpcTransport, "grpc"),
-        (ContextsClient, transports.ContextsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_datasets.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_datasets.py
index d937492337c9..3ffa7d3b3507 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_datasets.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_datasets.py
@@ -350,94 +350,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (
-            ConversationDatasetsClient,
-            transports.ConversationDatasetsGrpcTransport,
-            "grpc",
-        ),
-        (
-            ConversationDatasetsClient,
-            transports.ConversationDatasetsRestTransport,
-            "rest",
-        ),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_models.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_models.py
index 2e0cdc74d773..4688723fb4ac 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_models.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_models.py
@@ -347,86 +347,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (ConversationModelsClient, transports.ConversationModelsGrpcTransport, "grpc"),
-        (ConversationModelsClient, transports.ConversationModelsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_profiles.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_profiles.py
index 012145121162..b778e7517fd1 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_profiles.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversation_profiles.py
@@ -352,94 +352,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (
-            ConversationProfilesClient,
-            transports.ConversationProfilesGrpcTransport,
-            "grpc",
-        ),
-        (
-            ConversationProfilesClient,
-            transports.ConversationProfilesRestTransport,
-            "rest",
-        ),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversations.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversations.py
index 96736eb97f6b..c03e3d7a85da 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversations.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_conversations.py
@@ -327,86 +327,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (ConversationsClient, transports.ConversationsGrpcTransport, "grpc"),
-        (ConversationsClient, transports.ConversationsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_documents.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_documents.py
index 0d90bcbdbfed..e2eaaeb2d2ad 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_documents.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_documents.py
@@ -311,86 +311,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (DocumentsClient, transports.DocumentsGrpcTransport, "grpc"),
-        (DocumentsClient, transports.DocumentsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_encryption_spec_service.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_encryption_spec_service.py
index fe718c9e9a8c..28bca7237b05 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_encryption_spec_service.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_encryption_spec_service.py
@@ -346,94 +346,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (
-            EncryptionSpecServiceClient,
-            transports.EncryptionSpecServiceGrpcTransport,
-            "grpc",
-        ),
-        (
-            EncryptionSpecServiceClient,
-            transports.EncryptionSpecServiceRestTransport,
-            "rest",
-        ),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_entity_types.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_entity_types.py
index c1330c3962db..781871041cee 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_entity_types.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_entity_types.py
@@ -314,86 +314,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (EntityTypesClient, transports.EntityTypesGrpcTransport, "grpc"),
-        (EntityTypesClient, transports.EntityTypesRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_environments.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_environments.py
index be44a2780efd..f5675008c666 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_environments.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_environments.py
@@ -307,86 +307,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (EnvironmentsClient, transports.EnvironmentsGrpcTransport, "grpc"),
-        (EnvironmentsClient, transports.EnvironmentsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_fulfillments.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_fulfillments.py
index 25353f53f6bb..62996146b254 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_fulfillments.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_fulfillments.py
@@ -306,86 +306,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (FulfillmentsClient, transports.FulfillmentsGrpcTransport, "grpc"),
-        (FulfillmentsClient, transports.FulfillmentsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_generators.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_generators.py
index 8db7a273a509..4f31d0cd1d14 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_generators.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_generators.py
@@ -300,86 +300,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (GeneratorsClient, transports.GeneratorsGrpcTransport, "grpc"),
-        (GeneratorsClient, transports.GeneratorsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_intents.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_intents.py
index 8a3ed9a29649..92f9e4e9b94c 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_intents.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_intents.py
@@ -299,86 +299,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (IntentsClient, transports.IntentsGrpcTransport, "grpc"),
-        (IntentsClient, transports.IntentsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_knowledge_bases.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_knowledge_bases.py
index 979d3cecd153..8c17c9f38c32 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_knowledge_bases.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_knowledge_bases.py
@@ -322,86 +322,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (KnowledgeBasesClient, transports.KnowledgeBasesGrpcTransport, "grpc"),
-        (KnowledgeBasesClient, transports.KnowledgeBasesRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_participants.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_participants.py
index f01e31dbdb65..fdee0a1a74d8 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_participants.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_participants.py
@@ -311,86 +311,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (ParticipantsClient, transports.ParticipantsGrpcTransport, "grpc"),
-        (ParticipantsClient, transports.ParticipantsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_session_entity_types.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_session_entity_types.py
index 9f3d5af4f5d5..2d2f36b11efc 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_session_entity_types.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_session_entity_types.py
@@ -338,86 +338,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (SessionEntityTypesClient, transports.SessionEntityTypesGrpcTransport, "grpc"),
-        (SessionEntityTypesClient, transports.SessionEntityTypesRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_sessions.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_sessions.py
index 79cb10259fa8..e3e76027a20b 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_sessions.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_sessions.py
@@ -298,86 +298,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (SessionsClient, transports.SessionsGrpcTransport, "grpc"),
-        (SessionsClient, transports.SessionsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [
diff --git a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_versions.py b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_versions.py
index 674f27defcc7..82624a0aaa4f 100644
--- a/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_versions.py
+++ b/packages/google-cloud-dialogflow/tests/unit/gapic/dialogflow_v2/test_versions.py
@@ -295,86 +295,6 @@ def test__get_universe_domain():
     assert str(excinfo.value) == "Universe Domain cannot be an empty string."
 
 
-@pytest.mark.parametrize(
-    "client_class,transport_class,transport_name",
-    [
-        (VersionsClient, transports.VersionsGrpcTransport, "grpc"),
-        (VersionsClient, transports.VersionsRestTransport, "rest"),
-    ],
-)
-def test__validate_universe_domain(client_class, transport_class, transport_name):
-    client = client_class(
-        transport=transport_class(credentials=ga_credentials.AnonymousCredentials())
-    )
-    assert client._validate_universe_domain() == True
-
-    # Test the case when universe is already validated.
-    assert client._validate_universe_domain() == True
-
-    if transport_name == "grpc":
-        # Test the case where credentials are provided by the
-        # `local_channel_credentials`. The default universes in both match.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        client = client_class(transport=transport_class(channel=channel))
-        assert client._validate_universe_domain() == True
-
-        # Test the case where credentials do not exist: e.g. a transport is provided
-        # with no credentials. Validation should still succeed because there is no
-        # mismatch with non-existent credentials.
-        channel = grpc.secure_channel(
-            "http://localhost/", grpc.local_channel_credentials()
-        )
-        transport = transport_class(channel=channel)
-        transport._credentials = None
-        client = client_class(transport=transport)
-        assert client._validate_universe_domain() == True
-
-    # TODO: This is needed to cater for older versions of google-auth
-    # Make this test unconditional once the minimum supported version of
-    # google-auth becomes 2.23.0 or higher.
-    google_auth_major, google_auth_minor = [
-        int(part) for part in google.auth.__version__.split(".")[0:2]
-    ]
-    if google_auth_major > 2 or (google_auth_major == 2 and google_auth_minor >= 23):
-        credentials = ga_credentials.AnonymousCredentials()
-        credentials._universe_domain = "foo.com"
-        # Test the case when there is a universe mismatch from the credentials.
-        client = client_class(transport=transport_class(credentials=credentials))
-        with pytest.raises(ValueError) as excinfo:
-            client._validate_universe_domain()
-        assert (
-            str(excinfo.value)
-            == "The configured universe domain (googleapis.com) does not match the universe domain found in the credentials (foo.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-        )
-
-        # Test the case when there is a universe mismatch from the client.
-        #
-        # TODO: Make this test unconditional once the minimum supported version of
-        # google-api-core becomes 2.15.0 or higher.
-        api_core_major, api_core_minor = [
-            int(part) for part in api_core_version.__version__.split(".")[0:2]
-        ]
-        if api_core_major > 2 or (api_core_major == 2 and api_core_minor >= 15):
-            client = client_class(
-                client_options={"universe_domain": "bar.com"},
-                transport=transport_class(
-                    credentials=ga_credentials.AnonymousCredentials(),
-                ),
-            )
-            with pytest.raises(ValueError) as excinfo:
-                client._validate_universe_domain()
-            assert (
-                str(excinfo.value)
-                == "The configured universe domain (bar.com) does not match the universe domain found in the credentials (googleapis.com). If you haven't configured the universe domain explicitly, `googleapis.com` is the default."
-            )
-
-    # Test that ValueError is raised if universe_domain is provided via client options and credentials is None
-    with pytest.raises(ValueError):
-        client._compare_universes("foo.bar", None)
-
-
 @pytest.mark.parametrize(
     "client_class,transport_name",
     [