A lot of it depends on the instance. I think there's a little bit of a smartest bears type of problem going on, with a lot of the bad-faith content coming from just ignorant and abrasive people being sincerely ignorant and abrasive, not anything that's a bot or a deliberate troll.
Personally, I've done some rounds of unsubscribing from tech and politics subs on lemmy.ml and lemmy.world, and when I've done that my amount of toxic content and interactions went way down. I think the prevalence of the exact same thing on the tech subs points to it probably being just a bad-person problem in large proportion, although I'm sure deliberate malfeasance is at the root of some of it also.