I think their audience churn is just really high. So the YouTubers have to reach farther and farther for new viewers and engagement.

You search for something to confirm your thoughts, you find some of these commentators, and it is entertaining for awhile. But, after watching so many hours of their content, you no longer need to. You can predict their reaction and opinions. Why bother wasting the time to watch the video? That's why I think they have so much churn after awhile. Audience leaves because it's predictable content. The thumbnail tells you everything.

The drama farming eventually blows back on you, and these mid to big channels inevitably reap a shitstorm, or splinter internally.