For most of its history, Reddit didn't have an algorithm that promoted stories beyond upvotes and time since posting, that might even still be the case. Despite this, we have still seen a steady trend toward extreme views on the platform. To be fair, it has the reputation (at least in some circles) of being the most redeemable of the major social media platforms, probably thanks to the simplicity of its algorithm. Unfortunately, that's not saying much, it's a low bar to clear. What explains the polarization of Reddit in the absence of a bouncer amplifying extremism?
I think there is a significant percentage of users that do not initiate extreme content but participate in amplifying it. They may even find it problematic, but they really don't like the extreme views they hear on the other side. Or maybe it is the content they came to see out of morbid curiosity, something I am guilty of sometimes. The bar is so crowded because people find it preferable to the empty one down the street that has the expectation that people behave respectfully.
Incredible presentation, but I think the awareness we need to spread is a movement away from social media in general. As a social outlet it is generally incompatible with healthy social functioning and individual wellbeing. Face-to-face interaction has inherent guardrails for avoiding these problems and supporting the kind of social experience that we are really looking for.