4chan was simply where everyone banned for extreme views everywhere else went because there were no rules or close to none.
Now as algorithms of social media sites have been chosen to dictate our daily news cycle, discussion topics and visibility of culture by engagement metrics alone, as are dominated by flashy, extremist content that appeals to our lowest instincts. Before humans curated content by trying to use human reasoning instead of relying on instinct alone. I think we have taken a step backwards in evolution culturally.