Yes, in my opinion it is. Think about abuse in other contexts to put it in perspective. If a teacher in the middle of giving a homework assignment had said the same thing, would that be okay? What about a police officer who pulled someone over during a traffic stop? What about a customer at a drive thru saying this into the speaker?

This is not a random person on the street corner shouting at other random passers by. This guy is in a position of power over the people he is communicating with.