Social media has given a voice to people who up until the invention of social media would’ve been laughed at to their face for saying something as stupid as the things they say, and those people find communities of other like minded people who then go on to believe that all of society must think that way since they found a niche subreddit with 1000 members who think like they do. It’s like an infinitely compounding Dunning-Kruger effect. Dumb people who are too dumb to know they’re dumb find other dumb people who are too dumb to know they’re dumb, and then individual people hear those two dumb people agreeing with each other and think that they’re right, so the individual changes their views to fit the views of the dumb people. And then another individual sees three dumb people agreeing and it goes on and on. It’s a compounding Dunning-Kruger effect mixed with the instinctual desire to be included and accepted which leads to the slow dumbing down of our society.