I'm not sure I'd have uploaded that particular clip personally (and I know it wasn't you Dan)
I had a similar outburst the other day with an idiot driver who indicated right on the carpark and started to move in that direction before changing his mind and veering left right into my path causing me to brake considerably more sharply than I'd have liked.
I haven't had a total lack of control with a motorist for ages, and it had been a particularly crappy week at work so I lost the plot almost to the extremes of the guy in the clip. The motorist's response? "Have you finished?"
I decided I had, called him a rude name and left.
Lots of us have those moments, we just don't broadcast them. This is probably my main reason not to have a head cam.