This is unintuitive, but the TL;DR is that files will never change on PyPI, but (previously) a user could upload a new file to a release years after their last upload to that release. This has some legitimate use cases (like allowing people to support new Python versions without bumping a package’s version), but also makes introduces challenges around locking and release security that are elaborated in the thread linked by the blog post.
I agree this could probably be ratcheted down from 14 days over time, though.
You can’t go back later and add “evil.py” to a bunch of existing release files, but you could previously go find a bunch of releases that didn’t have arm64 files, publish malicious ones, and use that to catch people using those versions on arm64 systems
...why Python is just breaking compatibility so bad with new version it needs that ?