Simple answer is - because whites are excluded in every single advertisement of this and left likes to blame whites for existing. And I know I am ruffling some feather and that most of left doesn’t actually do that, but the loud and visible part does. And I also once fell for that and became pretty pissed at the whole idea of diversity, it felt forced and weird. Only I learned later that I was fed the cases where it was badly applied…most people aren’t, however, inquisitive enough to actually expand horizons.