Its a combination of representation and fetishization. Most people who cry out for representation are incapable of producing any work of art. Let alone an interesting engaging one. Hence why most modern media, which is dominated by these types, has gone to shit. As the saying goes "garbage in, garbage out."
Second Part: "White Male Hate"
Inevitably members of the first group grow to hate white male characters because they hate whites and males. This group is leftist. It subscribes to the modern leftist view of the world. That all males are sexist and privileged. That all whites are racist and privileged. That non-whites and to a lesser extent non-males are oppressed. Its pretty clear that once someone hates the real world equivalent, they are gonna hate the fictional version of that thing.
In addition, there is the belief that one can only find representation in characters that look or act like you. In other words, a black boy isn't gonna find such inspiration in superman as a white boy.
TLDR: Gotta make things black for "equality", "justice" and "representation".
Because taking something existing and appropriating it is easier and cheaper than creating something original. See: Every western remake of great Asian films. It's also not necessarily just black people blackwashing, because the film industry isn't all that colorful (harrhar). White executives and producers know that right now, it pays well, because there's a crowd for it, it's easy money.
Case in Point: Terry Pratchett's "The Watch" - see KF discussion.
The novels incorporate a nuanced discussion of tensions between policing and being policed, with different races playing an important point (A story that is more current than ever) that even has what I guess we would now call a trans character - except with nuance and interesting twists *
The American film adaptation features a flamboyant tranny and the pudgy white woman is turned into a badass black chick. The original tensions between humans, trolls and dwarves that mimic the tensions of our world's cultural tensions in all their subtleties are utterly discarded in favor of flat multi-culti easy-to-digest moralism.
The showrunner and screenwriter is the pastiest cracker you've ever seen.
There's a whole subgenre of fx. sci-fi that can be genuinely interesting called "afrofuturism", which incorporates a lot of old-african tribal mysticism into sci-fi, just like the industrial revolution is incorporated to create steampunk. That sort of thing is engaging to read because to people who have no connection to Africa, it's fresh, it's new. One novella that incorporates african culture, a coming-of-age story + colonialism into a decent narrative is Binti (though the author is a bit morally heavy handed). But to write something like that you'd have to actually study other cultures, you'd have to engage with history. Why do that when you can just repaint a character and call that revolutionary?
*if anyone is curious - the character is a female dwarf police(wo)man. Outsiders view all dwarves as male because all dwarves, including girl dwarves, have beards. During the book, the character notices that she likes human female attire and mannerisms, but feels these to be at odds with her gruff dwarven culture ("The axe") and her position as a policewoman, which requires her to exhude intimidation and/or authority.
She ultimately decides that she should not allow others to define her though, just starts applying some light makeup to accentuate her femininity, and carries on as normal - because she knows she is most defined by her actions and is more than just her gender and cultural history.
>Why do people black wash characters Niggers. They do this so they have something to cling to which will last beyond their self-afflicted meaningless existences. >Why do people hate white males so much Jews. The white male as a villain archetype works perfectly for them for a multitude of reasons.