Those are good points. Although if the cop had just refrained from claiming he’ll make up charges, he’d probably still be on the force. A stern talking-to would be completely appropriate in this situation.
but this kid never had any intention of this being a civil interaction. if cameras caught random interactions, that's one thing. but this is different, imho. the cop was trapped. he had nothing on the kid, but he could not let the kid act that way. the cop didn't know it was a set-up until it was too late. that being said, the cop went to far.
if that was me, i would have called another cop to the scene, combed the car for violations and gotten ID to write the ticket. if he still refused ID, he goes in cuffs to the station house, gets a ticket once ID is verified and is sent on his way. walking back to his car. all the while i'm calling him sir in a monotone voice. i bet THAT video would not be on his website.