>>102914516idk it seems like you're kind of assuming there there is significantly more vtuber slop in comparison to other things which really isn't true, you just see more of it because you're using this board for vtubers. Slop is just everywhere in general because it has a low barrier for entry.
there are also many more niche vtubers who don't get much fanart, quality lewd fanart at that, so there's going to be a greater proportion of slop since there are many more people who can make slop than there are people who can draw and you can produce much more of it