My pet theory/explanation is that, the more people see things go wrong in society (or, rather, believe them to), the more they tend to become contrarians. They look for views and beliefs that are opposite to what people in authority say. It seems to be built into us, like a tribe of stone age people will question their leaders’ methods and decisions after a row of bad hunts and then desire to hunt in a new place, at a different time, using different techniques.

Modern information warfare appears to use that idea centrally. The far right has been indoctrinated to believe that the “establishment” they rebel against is left wing and that a hard turn towards right wing politics is needed. After Trump won in 2016 and they were officially in power, they splintered a bit until they found a new lore: “actually, we’re still being ruled by the left, they’re the deep state, the cabal, etc.” to rekindle the contrarian / siege mentality and come together again.

I see all that in tankies, too. Society feels like it’s going wrong, so they sponge up any reason they see to hate the “establishment,” which is where the already running information warfare provides them ample facts to blame liberals and hate western powers, etc.

Also, on the hostility… yeah. These echo chambers seem to almost intentionally breed a nastiness that shuts down any useful discussion. Try to defuse anger and you’re “whiteknighting,” try to point out that something decent is good and you’re “virtue signaling.” When these communities erupt into other spaces, they quickly drive out anyone discussing in good faith. Survival of the nastiest.