I'll try to explain then, cause I think there is a lot to it, but I am bad with words ^^" I'm also a Black cis woman, and on the asexual spectrum (aego to be exact). And I feel like I don't view fetishization in the same way most other people might. A lot of times when the word is used it seems to also imply "dehumanizing", which I don't think is true, especially when it comes to fictional content. If anything sometimes I can find comfort in the idea of a specific trait being someone's fetish; like a fetish for disability, portraying neurodivergence as something attractive and desirable, that can be treated lovingly. And admittedly I'm also weird when it comes to who I "relate" to or how much I don't insert myself into fiction.
I also believe fiction and reality have a more complex relationship than one affecting the other in a direct 1:1 correlation. And some cultures tend to interact with and separate fiction from reality in different ways (North American vs East Asian). The way I lean is that depictios in fiction aren't going to change people's perception of real life that easily, and that it's society's pre existing notions that affect mainstream media more than the other way around. And it's even more complex and individual for smaller niche work like fan fiction...
But I do think it's unfortunate that people don't really discuss raceplay in particular, because I think it is worth bringing up how common it is. Questions that can be asked like, do people even notice when it happens or when they are expressing it? Is it so mainstream as to be omnipresent? Even just what causes people to feel this way about Black people, or any particular human race?
I hope any of this makes sense, I may have rambled a bit too much.