I agree they both were wrong. However, that woman antagonized and made the situation what it was, filming it, etc. The guy in the truck shouldn't have gotten so pissed about it as hard as that may have been. Some things you just got to let go. Some people want to draw you into their misery.
Where I live, "keep right unless to pass" is so foreign to some people. It comes down to ego and attempting to control others behavior.
Like another poster here said, everyday, I hate people more and more.