If you think "not specifically a black story" is what makes anything "a white story," you will be getting shit because that's just bigotry.

The role of ethnicity in most caucasian-cast roles is surely negligible, since casting them is the default, and most stories are not about that because it is the background radiation of American culture. Even the best example of a new alternate character, Miles Morales, parallels a dude who grows up lower-class in NYC. Suffice it to say there's people like that who don't look like Pete.

Like, when Netflix adapts Death Note, there's no specific reason to say Light should've been black... because the source material is Japanese. It takes place in Japan, all the characters are Japanese, and it is very directly about Japanese mythology, so setting it in Seattle immediately means they can do whatever they want.

When they adapted Cowboy Bebop and actually made Jet Black black, there was no specific reason (name aside)... because he's from fucking Ganymede. The only character who's from Earth is Faye, who's from Singapore, which no longer exists. Does it matter that they cast a Hispanic woman? Who exactly is done a disservice, by that change?

Not every black actor playing a black character has to be "a black character." They're just people. Relax.