What's weird is that a large portion of the people who do this are white (or other majority) themselves. Medievalpoc, who does a lot of wanking about PoC erasure in history that may or may not have happened, turned out to be white themselves after someone did some tumblr digging. (Not that I condone hunting down evidence of people's race in order to prove them wrong.)

I think they just like to sound superior. They say they're not comfortable in the fandom but I doubt I'm going to see them acting to make other people more comfortable.