It’s like living in medium sized town
I really like that analogy and think it fits quite well! There are by far too many users to know them all, but as you scroll through your feed and all, you keep recognizing users who you once had a discussion with or who keep posting or commenting interesting stuff to your favorite communities.
Even during WW2 not the whole nation was purely Nazis. The majority was brainwashed and following the cult, yes. But even during its highest peak of popularity, there were always resisting forces against the regime. Right now facism and populism are on the rise again but if you ask me a lot of that is caused by (presumably Russian) troll armys on social media.