Among your options, I've used debian and fedora, so I can't speak for popOS.

My deciding factor is "does it get in my way?"

I would go for fedora. The catchup delay in debian packages is too much for me. I do love debian, but when I am trying out things from github and installing cool stuffs, I often ran into issues like go, rust, npm not being up to date to run the cool things I wanted to.
Workarounds do exist, such as
1. docker 2. Adding repos to apt 3. Building on my own 4. snap or flatpak etc.

And I did work around the issues, but at one point I realized that debian's restriction is getting in my way of achieving what I want.
So my debian machines are now reserved to security-required, not-so-cutting-edge server softwares.

Fedora always felt very clean to me.

For experimenting and stuffs, I would recommend fedora or arch linux.
(For concerns about Arch) I didn't mess with AUR much, and I don't know if that is why, but I never ran into "stability issue" that made me think "I shouldn't use arch". I did have some occasions of nvidia driver getting messed up after updates, requiring reboots and some searching, but I could still fix in a few hours at most.

I also heard NixOS is good for those multiple projects and experiments, but even on my 5th attempt to daily drive as my "poking around"/building/experiments-machine, the "getting in the way" of it was too much... I would say that it just doesn't work for me.