So what happens as America becomes more racially and gender identity divided?
Public schools wane and private, parochial, charter, home and voucher schooling will grow.
Welfare benefits for the poor fall. Welfare benefits are highest in places with very homogenous populations and cultures - we care most for the welfare of people like us. They are noticeably smaller in most traditionally diverse locations. Newly diverse locations with high benefits like CA are busy bribing all the different racial groups demanding rewards and no doubt will radically truncate benefits as soon as they go bankrupt.
Affirmative action will get so complex and cause so much rage that it will die of its own irrationality. When there was one set of 'victims' and one set of 'oppressors' the process was easy to organize, manage and ultimately limit. But the more identities there are, the more finely graded levels of 'victim' and 'oppressor' that must be accounted for, the more chaos and conflict, the less support there will be for the whole idea. Which politicians and elites have always liked far more than the public anyway.
Finally, as different states evolve to different 'identity' cultures there will be more and more pressure to loosen the Union. How can people lacking our identity possibly govern us justly? It will also lead to balkanization within states and even metro areas.
Maybe we'll end up like Classical Greece: 1500 city states fearing, hating and warring against each other with 'Empires' like Athens or Sparta rising and falling with the tide of human affairs.
It's all so very Progressive.