Let's see, Green people are from Venus, Blue from Jupiter and Red from Mars...
I think a good part of f&sf is that you can write characeters that are not only not of any race or color, but might not even be very human. Perhaps that's an older sf idea..
Or you could Jonathan Swift the whole mess and skin everybody and turn them inside out.
Or satire the issue, and write Farnham's Freehold.
I see other art forms appropriated by other ethnic groups, as a matter of desire or economics. Re; Asians in orchestras, or white kids playing blues.
I happen to know a litle about the latter, and there is now a group of African Americans "reclaiming their heritage" by playing Country blues in the style of their grandfathers, even though the intervening generation was almost all pale as snow. Go figure.
What is the reading preference of an "average" African American Teenager? Harry Potter? Alice Walker? "Blade" Comic books? I dont even want to guess. But i bet that Alice Walker makes a lot more money writing what she writes than if she did high fantasy, no matter the color of her protagonist.
And, the Litr'y arbiter of America is Oprah, and if she ever had an SF book in her Book Club, i must have missed it.
Peoples is too complicated for even the best of intentions to change. And you can't write stuff that you dont read, so the first step, if you wanted to invite diversity into SFF, is to bomb minority schools with SFF books.
But then on the other hand, having said that, it is a fact that SFF is the default genre for movies, and so everybody is exposed to that.. And Hogwarts and Xavier School are both pretty well integrated.
So, are fantasy gamers pure white? I hear that Korea is the land of role playing games, so what does that mean, diversity wise.