OK well you're not doing anything wrong. It's just that the default Godot physics server needs work. For what its worth, in this example that you've shown, the problem can be amended if you do the following:
-
In Project Settings -> Physics -> 3D
- Set Time Before Sleep to 0.25 or lower.
- Set Sleep Threshold Angular to 0.1.
-
You can also enable Continuous CD in the Rigid Bodies but that usually just helps with detecting collisions in fast-moving bodies.
Your other option is to replace the default GodotPhysics3D with another one, as has already been stated.
I wouldn't recommend submitting an issue to the developers. I'm pretty sure they're aware of the physics server shortcomings.