Well that doesn't happen because part of the current push for diversity is based on a response to power structures, i.e. it's not a simple question of tit-for-tat race-switching, but meant to redress an imbalance.
This concept of
imbalance isn't simply because "the majority of the USA was white for x number of years" or whatever -- as I understand it (could be wrong) the issue is not merely with the majority culture (
whatever that may be) for the sake of it, but more specifically
a legacy of inequity due to colonial history, exploitation, in some cases slavery, etc. which is very widely believed to be still be felt due to what I would describe as systemic inertia, rather than a cabal of cigar smoking old white men in towers, which the hysterical Twitter Mob would have you believe. Now you may accept this idea of systemic inequity or not, I'm not trying to convince anyone as this is a toy forum.
How such a legacy
may have come to be is a fascinating read starting with Jared Diamond's
Guns, Germs, and Steel: The Fates of Human Societies which may not be the final word on the topic but remains an excellent, cross-discplinary starting point filled with science and history.
(Many of you on this board have either inferred or come out and said that I'm a 'liberal' in a more or less gently pejorative sense that I hear many Americans use. Given my wide circle of acquaintances runs the gamut from radical leftists to Randian libertarians and republicans, I can assure you that's far too broad and simple of a brush to describe my socio-political leanings which are policy-driven rather than party-driven.)
I think that thanks to the Internet, the lowest common denominators in society are creating an artificial binary that serves to divide and distract us all, and this is what's driving the over-correction by insincere, money-hungry corporations with no vested interests beyond their coffers, and I've noticed (ha ha) that fandom tends to be reactive about this.
That being said, it makes perfect sense to me that there are entire segments of society that want to see themselves represented in mainstream media, which has ignored or sidelined them for many, many years and I think it's important, because the world is not what mainstream, big budget entertainment has shown us for a very long time.
I actually don't care if Mary Jane isn't a redhead. I love redheads and I've had the pleasure of having my life ruined by more than one. But it's not that important to me, your mileage may vary but I see a lot of these old stories as Shakespearean and open to interpretation, as I've said elsewhere.
But I also agree that taking an established and historically white intellectual property and slapping a person of colour on it or pandering to the LGBTQ+ demographic without regard to a meaningful narrative, is lazy and opportunistic.
It's not the end of the world, but it's also a missed opportunity to create something new and vibrant, which is an opportunity in general that corporations miss 50 times a day due to being conservative, predictable and boring.
Anyway, that's why they don't slap white males on stuff.