The dude had his wife and baby in the car and the motorcyclists had completely taken over the highway. Far too easy for some biker in a swarm like that to think a driver isn’t somehow being respectful enough and then start this type of mass criminality.
It’s likely a group of weekend warriors who lost control backing up such a tough guy or two in their group.
NYC used to have a huge Hells Angel club in lower Manhattan. They were responsible for a lot of violent crime and a few mini -riots.