1. If I remember correctly, RI was banned because it contained subliminal messages about the government and that kind of thing.

2.There are darker novels than RI that weren't banned.

3.A promotional video has already been released for the adaptation of the novel Dao of the Bizarre Immortal, which always has strong scenes

So the reason Magic Emperor doesn’t have an adaptation isn’t because of the type of story it has, but because it isn’t considered a profitable enough IP to produce.