I have two thoughts on this: One is that tools like scalafix no-doubt rely heavily on static analysis to ensure correctness of their program transformations. I'm not sure a hypothetical "pythonfix" tool will be quite as feasible for untyped code bases.

And also, the issue isn't really with library maintainers when it comes to Python syntax changes. It's with all the user code written in Python. I tried converting my programs from Scala 2.12 from 2.13, and I failed so hard. I couldn't justify the time commitment, even with tools like scalafix to automate stuff. It's just not that smart.

All this is to say, let's not pretend that breaking changes to a programming language are ok. If you have to do break stuff once or twice in the lifetime of your language, fine. But accepting breaking changes as the status-quo is a failure of a language, by definition, IMO.