A lot of times, it’s also caused by leadership not wanting to stir the pot, so they let way more slide than they should. I can speak from experience that, yeah, it can suck to have to pull people aside and go “What you just said is not acceptable, this is your warning.” But you have to do it. You have to cut off that rot before it spreads. And it will spread.
I’ve been in everything from guilds to Facebook groups where leaderships don’t want to go to bat for people the way they should, because they don’t want the confrontation, and that leadership style always ends in the group dying, or worse.
If you’re looking to socialize in an environment that does not tolerate that stuff, I know I’m biased, but I suggest the Chamber of Heart discord. You can more than likely find a guild that’s for good people too.
We do not tolerate racism, homophobia, transphobia, religious intolerances, sexism… none of it. End of story. You see it, and you can tell me or a moderator, and we will shut that 
down immediately.