Actually, much of the problem--the vast majority of it--comes from long term forced programs, usually coming from the Left, on diversity, ethnicity, and celebrating even encouraging in law, keeping ethnic and racial groups divided. It would take many generations to end this problem.
Put another way, the greatest harm to various racial and ethnic groups is they are kept separate by various means. So, instead of a national identity, we get each racial, ethnic, religious, etc., group doing their own unique things that keep them often separated in larger society. Without a defining language, culture, values, and identity, a nation isn't a nation. Switzerland and Japan are two nations that get this. They want and expect people who are citizens of their country to adopt and have those traits. Without them, they won't let someone become a citizen there.
For many minority groups in the US, the Left has done everything they can to keep them separated on the claim that their individual culture be preserved rather than they integrate with society taking in the best they have to offer in culture, values, etc. This results in tribalism. "Diversity" of this kind isn't inclusive, it is divisive. It separates and weakens all of society.
It can be ended, but it would take likely more than a century to do it. The further down the DEI road we go as a nation, the more we're going to end up a bunch of hating tribes squabbling over bullshit while no one can figure out why we're all now poor and fucked. Societies survive without hatred. That's how they're supposed to work. The Leftist concept of diversity, equality, and inclusion produces a society with endless hatred. That's the problem.