Very well to everything you just said. You don’t have to make yourself think something you don’t.
Well…I meannnnnnnnnnnn…There are more white people on earth than black people, I think (most probably, but I might be wrong). Therefore the chances of there being more stories written by white people are way higher. Just like people tend to gravitate towards people whom they feel look similar to them, or how murderers usually choose victims within their own race, etc. this is an instinctive thing, if you’re white, your MC will be white (in most cases, not all). Imagine if every single black user wrote good stories (I’m saying this, not because the stories by black people aren’t good, but because we all know that among all the written stories, there will always be ones that are unreadable, or ones that just aren’t to our liking, so imagine if ALL of them were top notch stories) with black MCs. Then the number of stories with black MCs would, logically, rise noticeably.
And you can’t really expect all white people to write stories with black MCs since then you have to represent all kinds of stuff that maybe white people wouldn’t know. And all of that is best represented by black people themselves. And now split that into two: maybe American white people would be able to represent black MCs better than European white people, since there are many countries in Europe where you can still barely see any people of color (or black in particular, but not only). And very few people will do a whole lot of research just to have a black MC, you know? You can misrepresent or poorly represent a character even as a secondary character, let alone a main one.
But there’s too much to talk about this topic.