The PEP is not superseded, still active. You got this quote from the "history of this PEP" section. This is not what the PEP currently mandates and it hasn't for 2.5 years: https://github.com/python/peps/pull/989
That was not the point. There was a time where the PEP specified that "python" means "python2" and it was indeed possible to have no "python" but still a Python (3) installation.