pypi is full of awful amateur libraries that don't work very well.
Finding a good one among 20 crappy clones is a chore, and the most downloaded ones are not necessarily the best options.
I personally just stick with whatever is on my distribution (debian) and very very seldom venture out to using something directly from pypi.
In any case python doesn't require many libraries, so most of my projects require no more than 2 or 3 dependencies. Where js projects require 50, so the risk of issues from a dependency changing API is not as big.
I need a scripting language with a robust library, and I’ve seem first hand how difficult NPM projects can become.