The Duncan, Fishburne, or Wright casting doesn't really bother me, as I look at these modern adaptations as an updating to contemporary times, much as DC and Marvel have contemporized their comics over the decades. It's dramatic license I'm willing to give a director as long as the character is believably drawn and the essential non-racial, non-ethnic, or universal aspects of a character can be transposed to a contemporary setting: irascibility, crankiness, peevishness, arrogance, etc. Superman was conceived in the 1930s when there were no black newspaper editors, so if a director wants to update that story to the 21st century, there's no reason not to have a black editor because it's entirely part of our times and rightly so. As long as the character is three-dimensional in his own right. Moreover, I don't see anything particularly white or black about Perry White or Commissioner Gordon, other than that at the time of the comics' conception it was the social reality for editors and police commissioners to be white.
Now if they wanted to make a period picture, a Superman in the 1930s, as an homage to the original comic, then a black Perry White wouldn't make much sense because it would be inaccurate and actually papering over the fact that there weren't any black editors in 1938. The period social reality would be essential. In any case, Duncan as Wilson Fisk is a failure not so much because Duncan is black and ethnically miscast, but because the character as written is clichéd and shallow, regardless of race. It wouldn't matter if a white actor played Fisk in the Johnson version. It would still be bad.
Now although I'm willing to allow some dramatic license, I do have a problem, though, when contemporary directors try to inject contemporary mores and states of mind into period characters. It's not only historically inaccurate, but downplays grim social realities of the past by projecting a wishful contemporary gaze onto it. An example is The Spanish Princess, a Starz series about Catherine of Aragon. It paints her mother, Queen Isabella of Spain, as a sword-wielding fierce warrior. It also shows Catherine as pretty handy with a sword, all in an attempt to backward-project a Black Widow kind of persona onto these historical personages. Neither of them were actually that. They were powerful and influential, but in the context of their times. The Starz depictions are contemporized fictions that actually distort the nature of their power and how they, as medieval women still navigated an über sexist culture to wield power and influence in their own way. Isabella was fierce, but not as a field commander or knight like Brienne of Tarth in GOT. Isabella was powerful as a strategist and commander in chief, and as a skilled international political maneuverer. The Starz depiction makes her into a contemporary wish-fulfillment cardboard character. It would've been so much more enlightening, interesting, and accurate to explore how a woman actually and rarely attained power, against all odds, in late-medieval europe. It would show us why they were truly unique.