In some sense people on common platforms (Facebook, Twitter, etc) have super filtered experience to only be really nice to each other, support their governments and definitely not think on their own.

Fediverse, 4chan or DNs have essentially everything that was kicked out of those platforms. For example, fediverse has big separate instances (~communities) with trolls, nazis, communists/socialists, manga people and software developers (if I'm missing any notable big instance, please let me know...).