For the second question, the Arch Wiki has loads of helpful information. It doesn't just talk about Arch stuff though, it goes over a bunch of programs and configurations.
Kinda just ideological commitment. I sorta just started using Linux right off the bat, the only time I wasn't a Linux user was way back when I was using the family Mac. Linux has gone quite far over the years, in quite a positive way.
Arch, becaus AUR and rolling. Alpine, because lightweight. opensuse tumbleweed, because rolling and SUSE does cool stuff. NixOS because declarative. Guix, because declarative and bootstrapping.
Those are just the distros I use, I'm sure others are nice too.
All of them, basically. Arguing with people on Discord got pretty wild sometimes, and one of them straight up pulled up https://slurs.info and tried to use as many as he could. I suppose trying to argue with those people was a mistake, but I didn't get doxxed so all's well that ends well.
In person? Most of the homophobic or transphobic ones, though I don't think most of them were personally directed at me. K*ke (I'm not Jewish) and n-word lover are also pretty bad.
It's more similar to not believing Goebbels radio broadcasts about the USSR. We don't distrust NED, the CIA, or the State Department just because they did something bad once, but because it is both a consistent pattern of spreading misinformation and because it is their stated purpose to rile up dissident groups in US opposed countries.
"A lot of what we do today was done covertly 25 years ago by the CIA" - then NED president Allen Weinstein
NED's President Carl Gershman said that the NED was created because "It would be terrible for democratic groups around the world to be seen as subsidized by the CIA."
It's literally a group that does CIA stuff, without using the CIA name.
I mostly just pretend that thing's can get better, if I just communism hard enough. Also sex and drugs.