It's worse than that (and, I think, mendaciously so). YouTube tries to steer you towards the highest-viewed, most popular stuff on whatever very narrow vertical you're in...or a vertical that their algorithms have decided is nearby. Which is why you see people--mostly kids--going from videos about video games to videos about how the feminisms are taking away our video games to the feminisms are destroying Western society to straight-up white-supremacist agitprop.
Reddit is by no means clean; they just don't care about, as opposed to actively facilitate, this stuff. But you're right in that there are deep problems on YouTube, too.
Hmm, maybe it's bad in different ways for different viewers.
For me, it seems so ruthlessly risk averse that if I watch one video, it fills my queue with every single thing that person ever made, to the detriment of other interests.
Does YouTube assume all humanity is completely obsessive, based on some subset of frequent users who probably behave that way?
Reddit is by no means clean; they just don't care about, as opposed to actively facilitate, this stuff. But you're right in that there are deep problems on YouTube, too.