Yes, and you're the one saying that that was stupid. Jesus. Are you even listening to yourself? Change has been happening for decades thank you. And it didn’t require “everyone” to care. Just enough people who were focused on progress instead of convincing themselves they’re the heroes of the story.
There's a difference between my recognising that black people simply want to be recognised as full human beings and you claiming that "for many whites, black people are some 'mysterious uncontacted tribe'".
If you can't see the difference, well, again, consider that you're a racist in the good old-fashioned sense of the word.
Maybe, like DiAngelo, it makes you feel better to think that most white people are like you and it's not simply a failing of your thinking and character. But as somebody who has actually experienced racism, I can say with confidence that even the old-school racists I've had the misfortune to deal with are less infuriating than the smug, neoracist "progressives" who think they understand black people because they read a book.
At least the old-school racists can sometimes be reasoned with.