This is insane. Apparently (at least on Debian) this can be circumvented by putting this in ~/.config/pip/pip.conf:
[global]
break-system-packages = true
I would have preferred single-version-externally-managed to keep fond memories of setuptools alive.
It becomes increasingly impossible to track down home directory pollution and config files in Python. Next step will be a Python registry on Linux. How about:
Hmm that still recommends that distros allow admins to install to /usr/local, albeit in such a way that it at least can't break the OS.
IMO the idea that a 'Linux admin' is better informed than a 'Linux user' is increasingly anachronistic. In most cases the admin is just the user running sudo. I'd suggest that such functionality should be enabled by installing some kind of OS package rather than being the default
