I don't mind it for supporting characteers like MJ, Heimdell, Valkryie. Wasn't a fan of race swapping actual important characters like Human Torch and Aquaman though.
Importance can be a bit subjective though. MJ, for example, is not only a key supporting character to Peter Parker (if not the most popular one), she is also his main, longest, and most popular love interest. I'm sure many people consider her important in the Spideyverse. Her race may not be a factor to the character, but I don't blame those that felt some type of way about a possible appearance change.
For example (As far as I know) Rhodey as a character isn't defined by his race. He could be racebent and his character doesn't change much, if at all. Yet, I'm sure a lot of us--if not, all of us--would not like such a change. One could fairly say that non-white characters aren't shown much, thus its not right or fair to racebend Rhodey. However, I'm all about consistency. I fear that one day, all the racebending is gonna bite black fans in particular in the ass, as a character we either love or have a lot of respect for ends up changed.
Also, on a personal level, I'm sure Heimdell, Valkyrie, and others (Valkyrie in particular) could have a lot of fans that have followed them throughout the years and are used to seeing them appear in a certain way. Those characters may not be the most important characters in the grand scheme of things, but I def don't blame their fans (or comic book readers in general) for wanting said characters to look a certain way, especially then the source material presented them that way for decades.
But black fans aren't the ones racebending. It's the big wigs in hollywood doing it. That whole thing with Donald Glover maybe being the next spiderman started when one of the white guys in casting said "why does peter have to be white?"
Black fans aren't the ones doing the racebending, but black fans (as a collective, not all) will support it when it appears "beneficial" for them to do so, and then complain when it isn't to their "benefit." It's not so different than what a lot of white fans do, when you think about it.
Spidey technically doesn't have to be white, that's true. However, Rhodey or Sam (MCU Sam, at least) don't have to be black either. Surely we'd all much prefer both of them to stay black, so I can understand fans giving a non-white Peter Parker a major push back.
That said, I'm not trying to pin it all on black fans, it wouldn't be fair. As you mentioned, they aren't the ones calling the shots in the board rooms, or even the majority of the comic book fanbase. I just have a rather hard line stance on racebending, across the board. Not a fan of it.
I heard this raceswapped mj described as "hipster" which is odd considering Zendaya has more of a model's body-type i.e tall and bony with no figure.
What's funny is Hollywood only being able to make poc characters as sidekicks/love interests but never the main hero. The Japanese have a plethora of heroes yet when it comes time to cast for the live action adaptation, the characters become white.
Akira, Dragon Ball Z, Death Note, Ghost in the Shell. Asians can't even play their own heroes. Son Goku is basically the Japanese Superman but there are still arguments to this very day made by white people that Goku isn't Asian because he's an alien.
Indeed, Hollywood is doing it often and I really, really, really don't like it. Death Note, Ghost in the Shell (especially that one. ScarJo as Motoko?!), DBZ, etc. The ancient one in Dr. Strange was turned into a white woman (with a rather silly reason given behind it, imho). We also know very well the known examples of Gods of Eygyt, Exodus, and so on.
In all, I just hope for consistency and as much as an adherence for the source material as possible (within reason, of course). Turning asian characters to white characters, especially when said anime/manga has strong/notable japanese roots, is deplorable. It's no different that if the MCU tried to racebend Wakandans. Thankfully, Marvel knows they couldn't get away from the potential outrage.
Honestly, we are very fortunate that Stan and Jack not only set Wakanda in Africa, but also made it an isolationist nation, something all subsequent BP writers followed and reemphasized many times over. It makes it extremely hard to racebend from a narrative standpoint, unless one significantly changes key elements of the BP mythos.
Hollywood latest racebendings seem to be nothing more than a way for them to garner attention to get people talking. Seeing as it sometimes backfires I think they'll start turning established straight characters gay for the live action movies.
I'm still upset at them for turning Mr.Terrific gay in Arrow. I don't have anything against gay people but we finally get a black hero adapted for a live action TV show and with all the jokes about quotas aside they really decided to hit two birds with one stone. It wasn't needed, tho I actually really like the guy who plays him.
Sexuality changes really depend on the popularity of the character and how much people would care. Mr. Terrific doesn't hold much of a fan base, therefore DC was able to change that with little to no pushback.
Now, compare that to those that hoped that Steve Rogers would be gay. The push back from fans was immense.
