I agree, it doesn't matter much. Just like frameworks and programming languages, they may be considered boring and aren't being hyped up, but the stable options are the safest. Ubuntu, Mint, Debian, OpenSuse and Fedora are go tos. When starting out you want information that is easy to find, I can personally attest that you will easily find information with those distros.

The bigger the distro, the more official support there is as well, instead of relying on community versions. Ubuntu and Fedora get a lot of dev love.

If you are willing to read up a bit more and re-install a few times, Arch Linux is another distro with a lot of community information online. But honestly for work, I would stick to old reliable Ubuntu.

If you want more up to date programs might also consider Linux Mint, Sometimes Ubuntu is a bit behind the curve on languages and such Mint is also Debian based so a lot of Ubuntu's help applies to mint and the mint support community is also pretty strong.

I started with Ubuntu for my development computer and am now running Mint because I needed more recent versions to test with. The servers are running ubuntu server though (since I try to develop ahead of the version on the server) so it works out.

One of the main difference between Ubuntu and Mint is the graphical desktop environment as well, isn't it? As far as I know, Ubuntu uses Unity whereas Mint offers 3 flavors: Cinnamon, MATE, Xfce. All those 3 DE-s give a more Windows-like user experience and probably make the transition easier for that reason alone.

Pop!_OS is another flavor of Ubuntu (just like Mint) tailored for developers. If I were to start with Linux today, as a developer, I'd probably give it a try.

For hardcore mode, pick Arch Linux, as this is where you will probably end up distrohopping eventually if you like to tinker with your system.