You mean that religious artist who recently fund a guro hating girlfriend :)?

I think the main reason for it disappearing is that people are not showing their interest. Vanila artists receive far more popularity and comments for their works while if you do guro you rather receive complains even from other people who like guro because the have different interests.
If you want it to stay alive for longer you need to tell those artists that their work is interesting to at least someone.
Like for example 442b on pixiv is doing very good work, but even entire 20 page manga receives juts very few comments while some valila artist who just throws single picture of the cute girl gets few times more.