The most toxic communities I know of are the Genshin community, Payday 2, FFXIV and source games communities in general.
Left 4 Dead 2 versus. I dare you to join a random match online and last longer than 10 minutes without getting kicked. Or just search for “left 4 dead 2 versus kicked” and you will find countless examples of people complaining about it.
It’s become a meme at this point and I’m pretty sure that people kick for fun although some claim that people kick you for not being good enough or too good. Just play with friends instead or play campaign, people are nice there.