A yellow light is technically a "clear the intersection" light -- you're SUPPOSED TO move into the intersection when you're making a left hand turn. If you don't have an opportunity while the light is green, you're supposed to clear the intersection (ie: make your turn) when the light is yellow. Obviously people are assholes and try to beat the yellow, so if you go when the light turns red because that's the only safe opportunity, a cop likely would never give you a ticket for that (would be more likely to give a ticket to a person running a yellow).

In this instance, though, the light was obviously green, meaning the truck driver made an unsafe turn. If the conditions were better, maybe the guy would have made the turn. Any time you're going against traffic, though, liability is basically automatically yours, regardless of situation.

That said, the guy in the truck made a mistake. Getting all pissy at him and yelling is only going to make him want to go on the defensive. There's not a lot of damage, and the dashcam driver will obviously get fully compensated. There's no point in getting an assault charge over a traffic incident (I say that as a warning, I don't know what dashcam driver actually did after the video, but if he got out and puffed up his chest and went at the guy, traffic incident or not, that's going to be assault).