FWIW, I’ve created PEP 704 as an alternative to this PEP, which I will withdraw should this PEP get accepted. It is intended to resolve the same concerns, albeit with a different approach: requiring virtual environments for pip install (and equivalents) and establishing a conventional name for virtual environments.
Personally, I’m ambivalent on which approach is picked between PEP 582 or that proposed PEP. 