Imagine if GNU released a new, highly backwards incompatible version of bash called Bash 6, and then some platforms kept /bin/bash as Bash 5 and introduced /bin/bash6, some systems replaced /bin/bash with Bash 6 and introduced /bin/bash5, and some systems removed /bin/bash entirely and /bin/bash6 was the only Bash on the system.
Python had the opportunity to be, and was, to some extent, just a standard part of a UNIX-like system, like bash. But now it's just another language where you need to care a lot about interpreter versions and how different distros package it differently and keeping code up to date to work with the latest Python and keeping Python up to date to work with the latest code.
This doesn't mean that Python is bad, but it would have been much more useful to me, and quite a few others, if it had stated a ubiquitous tool which is more like Bash and Perl.
As systems started shipping Python 3, the convention among most of them became to leave `python` as a Python 2 interpreter and then introduce `python3` as a Python 3 interpreter. As they then stopped shipping Python 2, they generally just removed /usr/bin/python, so the only Python on the system was /usr/bin/python3.
In my own scripts to build Google stuff, I always had to make a folder with a single script called `python` which would contain just `exec python3 "$@"`, and then prepend that directory to the `PATH` when invoking Google's tools.
Google eventually did update their stuff to work on systems where the only Python is `python3`, but man this transition was rough. As I understand it, Google had good reason to do it their way at the time too; there was simply no consistency in how systems handled the 2 -> 3 switch. I suspect that this is due to a severe lack of guidance from the Python foundation.