It feels like this is making up for the uncanny lack of unrest for the last few years despite everything that happened.
I think it was the unreality of it all. Trump elected, White Supremacist gatherings out in public celebrating, unprecedented lack of leadership. What do you when you are protesting systemic racism, and the president says "You know what, you're right. I am a White Supremacist, so are the cops, and you can't do anything about it, so shut up." Also, the president is wearing a clown suit when he says it, and the media is acting like that is perfectly normal.
It can't be real. But eventually people adapt to that reality and it isn't going to work this time deflecting it to "oh no, the looters, oh no, they have no moral authority now." They gave up every shred of plausible deniability the last few years, they elected Trump because they didn't want to be bothered having to deny it any more, and Trump still won't come out and deny it because that's the whole point.