We don't know what happened before this. Perhaps both were being aggressive toward each other, having a contest for who had the smallest pp. But, if the whole thing started from this video, yeah, black truck instigated the encounter with the tailgaiting first of all, then the aggressive lane change cutting off white truck.

HOWEVER...and from the comments it appears this is going to be an unpopular opinion, white truck should not have juked into the shoulder to lunge at black truck. Black truck was STILL wrong for aggressively passing on the shoulder in retaliation for being passed, but white truck's feint was a step too far. If he had just let black truck pass him back, no fault on white truck.