Citation required for every single thing you said.
No evidence I benefited from past nastiness any more or any less than any person alive today. The direct descendants of slaves are long-dead and the last people to come of age under institutional racial segregation in this country are past retirement.
No evidence the bag of crazy one finds in Robin DeAngelo (read her work, I did, and there's literally elementary school logic mistakes on every page), Ibram Kendi, or their many copycats actually does any good to anyone other than the consultants pocketing fees for their diversity training services.
Also no evidence that saying land acknowledgements ad nauseum, renaming columbus day, or prefacing all your statements with a header packet listing your ancestry and supposed guilt has the power to reach back in time and undo the slave trade or innoculate the natives against smallpox.