I used to be a redditor, so I know, redditors think they are smart due to subreddits being complete echo chambers.

you never have to interact with people who oppose your opinions. Instead, you hangout in a subreddit with thousands of other likeminded NPCs that constantly pat each other on the back about how intelligent and informed they are.

This is further compounded by power hungry mods that can ban "wrongthinking" users with impunity. So discourse has no chance to foster.