Re: 20 years is a lot of time.
Are people still using Windows 98 SE? No? Then why are they still using Python 2?
Because Python 2 is still being supported by its originators, which Windows 98 SE isn't.
Because they have big systems written using frameworks written in Python 2 and either the framework hasn't been migrated to Python 3 or the upgraded version isn't quite compatible with the old one and they can't see any reason to migrate.
Dropping support for Python 2 should have been done years ago! Not in 2015, maybe, but extending to, say, 2017 would have made more sense than 2020.