I think it's more about people using FFXIV as a tool to do 18+ activities, ignoring the semantics of if this is part of "online MMO culture" or not, it comes under the whole lewd/obscene section of the ToS which was quoted last time there was a big hufuff about this.
If people wanna do their 18+ stuff in game, stop advertising it in game and keep it private. There are plenty of Discords for this. I don't get how this is difficult.
