1. macOS ships a /usr/bin/python3 that is up-to-date at the time of the feature freeze of a major macOS release, e.g. macOS 11 ships Python 3.8.2 from February 2020.

2. /usr/bin/python being a symlink for python2.7 is entirely consistent with PEP 394 recommendations, especially the version before June 2019: https://raw.githubusercontent.com/python/peps/214736457f6d61...

  * Unix-like software distributions (including systems like Mac OS X and
    Cygwin) should install the ``python2`` command into the default path
    whenever a version of the Python 2 interpreter is installed, and the same
    for ``python3`` and the Python 3 interpreter.
  * When  invoked, ``python2`` should run some version of the Python 2
    interpreter, and ``python3`` should run some version of the Python 3
    interpreter.
  * If the ``python`` command is installed, it should invoke the same version of
    Python as the ``python2`` command (however, note that some distributions
    have already chosen to have ``python`` implement the ``python3``
    command; see the `Rationale`_ and `Migration Notes`_ below).

The 2019 update https://github.com/python/peps/commit/ae932bd6fd2c493d7d64ce... allowed more flexibility, but the old handling is still entirely okay.