I dunno... I know personally I wouldn't have a problem with someone painting themselves white to cosplay, because there's no meaningful cultural appropriation going on there, "white" being the dominant media culture. (I also totally get why no-one would want to - I mean, why contribute to the erasure?)

BUT. I wonder if in a world where racism had been erased - like, theoretically, Star Trek - you could paint your skin a "real" colour without it being problematic?