I guess it's been a while. Last time I played around with Linux properly was around 2009. Having worked with Ubuntu servers as recently as 2018 though I did find getting python 3.7 up and running a bit of a pain, with differences in the process for minor versions of Ubuntu.
Not to diminish any of your problems; and I'm aware that this is not (yet) reality in most places, but:
1.) I absolutely agree on the Ubuntu front (though I don't believe for a second that things are better elsewhere. E.g.: Python on Windows is way worse in my experience). But I dislike Ubuntu (and Debian, for that matter) for many related experiences I had in the past.
2.) I'd say, though, that you're missing out on good containerization solutions if you're wrestling with Python installations on a server distribution.
3.) Most importantly: Where things like Docker or LXC don't apply (or don't apply as much; like development/desktop usage), the single best concept I've encountered so far would be the way NixOS and Guix handle installations. I sincerely hope that model will take off in the next couple of years. And I'm pretty sure that if it takes off, it will be on either Linux (most likely) or BSD.
I've worked with Docker before but I found it too resource intensive on my local machine. I now use docker to get consistent deployments but for local dev I find it too heavy. I'll have to look into NixOS and Guix
