To be honest, its probably all about capital. I went to a comic book store in manhattan yesterday. About 70% of the customers were white, 29% were asian, and the other 1% was a mix between latino and african american. You're going to cater to the people who buy your comic books.
True, but a lot of brothas pay attention to the comics. Method Man, aka Johnny Blaze, Ghost Face aka Toney Starks, they even had a Wu-Tang comic (I have #0 and #1). even in college, there were comicbook geeks who were "thuggish". I had friend and roommate that was from St.Thomas (no nerd) and he was a graphic arts major who collected The Darkness.
I was a Joe Mad fan back when he inked Uncanny X-men.
But, I agree with what you are saying...
I still think that they need to have either Michael Jai White, Wesley Snipes or that African dude play Black Panther. And Michael Jai White to play Luke Cage.