The idea of "distros" for python is interesting, and to a certain extent has already happened: just look at Anaconda.
I've been using built-in environment isolation tools such as virtualenv for ages but have recently switched over to using miniconda for all things python. Among other things it has amazing support across all three major OS's, and I happen to be dealing with all three at any given time. Whether one uses miniconda, pipenv, virtualenv, or anything else like it, as far as I am concerned the days of ever using the system python are over. I will always create my own personal "distro" on the fly with full control over the python version and every add-on package.