Welcome to the world of commercial viability. Films are expensive to make & distribute. Is it really outrageous to design films that will have crossover appeal, to all races?
Incidentally, on the subject of diminishing an historical white character, what about Rosewood? John Singleton's account of the 1922 Florida massacre that has been virtually buried from mainstream history?
The film's star, Ving Rhames, plays fictional character, aptly named "Mann". Mann strongly influences the choices of Jon Voight's John Wright, a real character, who, along with his wife, Mary Jo, hid many Black residents, possibly saving them from the rampaging white mobs. Per the film, Wright is shown screwing his likely underage Black shop assistant. Later, he's depicted as taking in an injured resident because he wants the man's parcel of land. When Mann brings more people in need of refuge, Wright agrees to shelter them only after being shamed by the father of the shopgirl.
As the film's climax, Wright arranges for sympathetic brothers who operate a train to evacuate the women & children hiding in the swamps.
It's a pretty good, if neglected film, highlighting a disgraceful episode in US history (& one for which rare reparations were eventually made to survivors). I also get how tired audiences, & not just Black ones, are of white saviors. Hence the character of Mann. Furthermore, I don't know if the real John Wright was. motivated by greed or shame in hiding Black residents. All I can find from the histories is that he & his wife did hide them, putting their own children at some risk.
If Wright did as the movie portrays, then certainly you have a white character shown warts & all. If he didn't then there's your example of an historical film making a white character appear lesser than he actually was.