What happens if your project needs an update, but it will hose the OS? Do you expect someone working in Python in Windows who wants to distribute a datetime package should package for RPM and APT?

I used to think OS package managers should be the end-all be-all, but the use cases for OS package managers are very different from language runtimes. While different Linux distros were fighting between themselves, they completely ignored use cases for projects and language runtimes. Sadly, the result is a mess for everyone.

I think people need to figure out what approach works best for them. I'm of the opinion that any core technology to your business needs to be decoupled from the OS. It makes OS updates too messy and you're tethered to whatever the OS supports. My field uses a lot of Python and every company figured out quickly they need to run their own binaries in addition to packages.

At one company, they packaged up custom RPMs. It wouldn't be a problem to package up and distribute Python libraries. Others had their own package system (no OS or runtime fit their needs). It seems like most people use something like virtualenv.

Regrettably, this means there's no easy answer for people new to Python and the right choice will probably change as you grow. But I really think the answer is Python should come up with something that works for Python and let OSes do their thing.