[IshKebab]

You're trying to think of problems, not solutions.

It's pretty easy to think of a good solution with few enough downsides that overall the design is much better:

In the REPL only, if you type "exit" and press enter, it quits.

No changes to Python semantics required. All code still works. Much friendlier UX.

I wonder what dubious justification the Python Devs would come up with to avoid implementing that (and therefore admitting they've been wrong for 20 years). They'd probably try and claim it is more confusing to beginners or some nonsense like that.