Red Hat and other large companies have maintained Python for years after 2.7 died (EOL date was January 1st, 2020). IBM/Red Hat offer Python 2.7 including security fixes and bug fixes until 2024 (https://access.redhat.com/solutions/4455511).

Had he just provided patches to Python 2.7, nobody would've batted an eye. Instead, they created an alternative language that was completely different (https://web.archive.org/web/20161210161837/https://www.nafta...).

Founders and core devs indicated that the name was the only problem (https://github.com/naftaliharris/tauthon/issues/47#issuecomm...) and that even things like the header file names could continue to be named Python because of API compatibility.

You can fork any open source project you like, but you still need to stick follow trademark law. You can't just release Linux 2.7 because you disagree with breaking changes in 3.0 either, but you're free to take the Linux code and release Twonux if you really care.