This was inspired by the demise of the Pong example in older versions of Godot and was my first project using Godot or really any game engine for that matter.
I wanted a basic game which leveraged as many features of Godot as I had learned while still trying to minimize the amount of scripting needed. My hope is that it will help some other people just learning Godot for the first time to wrap their head around some concepts.
Having said that, I'm open to pull requests if there are some other Godot-isms or even basic programming approaches which will simplify this any further. I'm not looking to add a bunch of crazy functionality to this, but it would be nice to keep it updated from one version to the next as features change if it makes sense to do so and simplifies the design further.
You should be able to import this as a project in Godot and immediately run it with F5. The default input mappings use the D-pad on the first and second detected joysticks or W+A and Up+Down on the keyboard for left and right player respectively. You can mix and match as desired and Godot even handles hot plugging a joystick correctly mid-game.
The ball increases in speed up to a certain threshold to try to prevent a stalemate. The first player to reach eleven points "wins" at which point, the game resets. Press F8 to exit.
The game isn't supposed to be an exact replica of the original, but I think most of the ideas in use are faithful to it.