You do not need interpreter for python, you can convert .py file to .exe with pyinstaller.
That’s correct. The rule is just an example, as you are allowed to not do that with python or inform 7 if you want.
Will this still work if you're using something like Pyxel or Pygame?
Yeah, you can import Pygame into your .py script and still compile the script and its assets into 1 exe file using pyinstaller. Never heard of Pyxel..