I installed the server OS that all those other distros are based on...

Why would it be for old hardware? Old packages for old hardware? I had very many driver issues on an old dual core Intel laptop with Debian. While Arch ran flawlessly. The drivers when you do an archinstall and pick the intel option are great. Instead of fumbling around in synaptic with free non free contrib bullshit.

Do you actually use it or are you just saying this? I am not interested in making 50 startup scripts for the absolute joke that is runit.

Old kernel, old firmware, old libraries like libva so hardware accelerated video decoding didn't work, had to add bunch of backports or testing packages to make it work