Alright, I know there were some posts upthread about the subject of fidelity in worldbuilding but I can't be bothered to go did them up to respond to someone directly. So instead of just going to go off.
One thing that always crops up in these kinds of discussions is the issue of worldbuilding, often with a lot of stressing how you can have POC in your fantasy story, but there needs to be some good and deep worldbuilding behind to to make it make sense from a geographical, anthropological, or cultural perspective. People tend to very deliberately stress the need for this thought and care put into the writing in order for a POC plentiful fantasy universe to be accepted.
My answer to this is to ask what the fuck PCP they've smoking that they think a fantasy world always needs to "make sense". Maybe to a small subset of readers this is super important, but for the most part it is really not that big a deal and isn't required for a fantasy story to be good or successful. Wheel of Time's world is stupid and dumb, and it's one of the most successful fantasy stories ever. Name of the Wind barely even has a world that's described in any real detail, and people love the shit out of that book. They eat it's ass. GRRM basically threw disparate European cultures at South America sized Britain shape, plopped a Conan the Barbarian setting beside it, and justified it by making it feel real. It got a wildly pilopukar TV show where the world makes even less sense. People nitpick these series, but the story's didn't fall apart and the books burst into flames by the lack of sense made of their worlds. It's achieving suspension of disbelief with good writing in your stupid-ass fantasy world that matters.
The fact that the subject comes out mostly strongly in these discussions says more about people's perceptions and biases about race and fantasy that it does about writing. To people medieval Europe is just fantasy, if you have that you barely have to world build shit. But if POC appear in a more than antagonistic, sidekick, or incidental role then the tendency is to question their existence because the ideological construct of fantasy that exist in people's brain meat doesn't include them.
They POC them almost like they would an anachronism like if a refrigerator or a chainsaw showed up. People may as well literally think that black people were invented in April 1861 for all it matters.