My take for a while has been that authoritarian ideas (both hard right and hard left) dominate on social media because of the short form short attention span format. Authoritarianism tends to run on simple slogans, grievances, and identity politics. That stuff is very well suited to 140 characters, memes, and short videos.

Liberal ideas require more explaining and historical context, and they don’t play well when everyone has been triggered and trolled into limbic system mode by rage bait.

Liberal politics speaks to the neocortex. Authoritarianism speaks to the brain stem.