If you want to see a place that has a toxic culture because it is filled with, well, arseholes - then you need to have a look at Wikipedia.
In fact, if you want to see how bad it can get, then you need to look at something I'm unfortunately responsible for starting - the Wikipedia Administrators' Noticeboard:
https://en.wikipedia.org/wiki/Wikipedia:Administrators%27_no...
Even worse is the incidents section of that noticeboard:
https://en.wikipedia.org/wiki/Wikipedia:Administrators%27_no...
It's very, very hard to edit on Wikipedia these days. If you have any mental instability whatsoever, I strongly urge you to avoid editing Wikipedia like the plague. It's very unlikely you'll be able to change the culture, good people with great reputations in the community have tried but the culture is so bad now that it's impossible to fix it as it stands.