I'm decent with the filters and the secret filters. It's mostly that a lot of authors will tag with useless sentences rather than actual key terms. Let's say if you filter out m/m you'll still have to filter out Harry/Tom Riddle, Harry/Voldemort, Harry/Tom Riddle|Voldemort, Harry/Draco, Harry/Snape, Harry/Draco/Snape, Harry/Lucius, slash, pre-slash, maybe slash, because authors sometimes don't tag m/m. Now imagine having to get that granular for everything.

The slash itself isn't really the problem, although I generally don't read it. It's that AO3's preferred plot type is out-of-character romances. I get that the target demographic there is 15-30 y.o. women, and that's what's popular with that population, but finding anything else is a difficult slog. It's fucking insane for me that they have a filter for underage sex/porn stories but not genre.