If you see someone who is bigger than you get out of their car, while you are already in a heated exchange, have some self-preservation in you to be able to react in a way that this mentally unwell piece of shit can't just grab you by the neck and slam you down. Get ready to fight, or please just leave the scene as quickly and safely as you can.

I don't blame the biker. All around the world "people" are becoming more and more like animals. Acknowledge this, and prepare yourself for anything these animals might do. :-/