IMO pip has a lot of technical debt which we would need to pay off before we could add a lot of extra complexity. So while “just add the functionality to pip” is plausible, it’s not a quick option.
Also, I don’t know if the wider workflow management aspects that I believe people are asking for would fit as well into pip. The debate over a pip run command suggests that this might be a tough path to follow.
Basically, and I think someone mentioned this previously, I think a lot of the actual user complaints are around environment management, and that’s the area that is least likely to fit into pip.