The rager acted on what he perceived. He was probably tired of slamming on his brakes every time she got off the throttle while she left what he might have thought is too much room she left. I'm saying the same thing over again, but why ride that way in the left lane? Get over if you don't want to shift and maintain the flow of traffic.
She is actually lucky he didn't use his vehicle as a weapon. Making her a skidmark would have been a traffic infraction, "I couldn't stop in time."
There's a reason I don't act like "it's their problem" as you said. Laws of physics say they can make it my problem. And your CCW isn't going to help you in or after a TC on a bike.