If people were given the chance to be reborn a different race there would be an overwhelming amount of people choosing to come back as white. Outside of thecoli there a lot of black people with self hate that jump at the chance at any sort of white validation. This is 10x worse outside the black community especially in Asian and Hispanic communities. I’m convinced if you ran this test in Latin America the mestizo/black populations would disappear in a generation.
Me personally, I have too much pride to ever make that choice and not hate myself for it. Choosing not to be reincarnated would probably be the best.