N word isn't that big of a deal in kpop tho, Giselle got away with ease so ahyeon would also had been just fine, there was no need for her to disappear
Well... Giselle's rough couple years is partly due to that, a lot of people weren't happy about it. The other part of it was her not matching the other members in terms of dance performance proficiency. However, once she really improved her dancing, notice how you don't really hear much hate towards her these days. So it's pretty much a big deal until it isn't, and since Giselle apologized and hasn't made the same mistake twice, there's only so much that can be said. And I say that as a black kpop fan.
When it comes to Ahyeon though, I agree that I don't think that's the reason why she hasn't been seen. If that incident had become as big as the Chaeyoung Sid Vicious shirt incident, I could see YG cutting their losses and sending her on her way. If she ended up leaving, it's probably something completely unrelated unless YG really didn't want to take their chances, since there's also the big elephant in the room regarding Blackpink.