I did not get the assault on camera -- what follows is a lot of talking and a de-escalation of what had become physical thanks to passengers that took action. The older guy should not have touched the young guy.
A young performer asked this man to move. He refused and instructed the group of performers to get out. I didn't see the young man touch the guy but the guy either hit or shoved the young man -- it looked like he assaulted the Performerers
The guy said get off the train. He did not want blaring music and entertainment.
He got physical. Group of diverse NYers including a woman made peace. The kids did get off at the next stop.
The man acted like he was auditioning for Dirty Harry minus the gun.