I'm really struggling writing a proper test for this warning. Adding another test based on the stuff in setuptools/tests/test_bdist_egg.py was not successful.

Finally got around, writing a test for the new warning.

I don't know the best replacement. Doing a quick search, I see zipapp seems to implement something very similar. I haven't personally spent much time creating these apps nor have I seen them in the wild, so I can't speak to the use cases.

Any updates on this one?

Thanks for the ping. I can't imagine belaboring this issue any longer. I agree it would be nice to provide a replacement, but one of the goals of the PyPA has been to simplify the tool chains and limit the supported use-cases, and I think this is one of those cases, so there is no recommended replacement, at least from PyPA.

Thanks for the ping. I can't imagine belaboring this issue any longer.

Agreed. Assuming we give a sufficiently long deprecation period, there's always the opportunity to update the warning message if this niche in the ecosystem really needs to be filled.