Given that they're extremely story-oriented games whose gameplay revolves almost entirely around figuring out where that story is going, I'd imagine most people.
That said, the "who cares about spoilers in a fighting game" thing does disregard the fact that many people prefer the surprise of encountering unlocks and the like while playing the game, rather than being told about them beforehand. It'd be unreasonable to expect people to mark spoilers for discussing official trailer material, especially in a discussion that's obviously about that (if somebody really wants to go in blind, it's their responsibility to avoid such discussions), but openly talking about something that's been datamined is potentially inconsiderate, depending on the nature of it (i.e. "this one music track sounds good" is not a spoiler, "the final boss of the story thing is a chicken made of lego" would be)
Yeah unlocking an alternate hat is such a spoiler. ---