That seems to be a pretty big and weird theme of his. For a long time he was focused on creationists (first VenomFangX, then Ray Comfort), and at the time that didn't seem to be a big deal, because creationism deserves mockery. Then he did a hard pivot and obsessed over Anita Sarkeesian for years, and that started to make it clear that it he was more interested in hosting a 2 Minutes Hate, and didn't care as much about the subject his targets cared about.

Got to do what sells. There’s more than one subreddit dedicated to hating on everything he does up to the minute. I’d imagine there’s a large market for it on YouTube. View counts push creators to certain niches as much as personal beliefs.