I watched some of the video he posted above, and I don't see the kids behavior any better that those black nationalists/black religious group, or who ever they are. Just because of group of black men is acting weird and being offensive is no damn excuse for those kids to get out of hand.
I live in Trump country, and I can imagine what these kids are like. They are mostly all white kids who go to a Catholic school and are very sheltered. For many of them, this could be their first time getting out of state, seeing a big city, and they aren't used to all the diversity. Yes, I have seen black groups like that before, and I walk by. For a group of teen boys like them, brought up sheltered and conservative, and not used to such diversity and openness, they were feeling shocked and outraged and acted out as such. People who defend these kids feel the same way. They take a look at those black men, listen to what they are saying, and get outraged.
Somebody like me... I have no issue minding my business I walk by people like that, and I understand we all have freedom of speech. I grew up in a city with a lot of diversity, and racial diversity does not offend me. People of all colors have offensive views, and I have heard their views. Big deal. I have never felt compelled to act out and confront such groups in any way, and plus, they like it when challenged. They like to argue with people.
Those kids behave like little assholes who have never seen a big city before. Who knew black men could act like that? Who knew native people play drums in public? And because they didn't walk past that black group and ignore their BS, they are not any damn better than them.