This doesn't end well for anyone involved.
Lane-splitting is perhaps the biggest thing motorcyclists do that pisses off drivers. I ride a motorcycle and can say that as a driver I have been frustrated many times by a biker appearing out of nowhere next to my car. In California the practice is legal, but that doesn't mean motorists like it. Case in point: This video shot on a dash cam in Los Angeles and featuring a ton of bikers splitting lanes during rush hour. Off camera one of the bikers smacks a white Ford Ranger for getting too close to his fellow riders.
That's when all hell breaks loose. The Ranger dekes left, causing the motorcyclist to lose control and crash. But since this is rush hour the Ford isn't able to speed away. The angry biker jumps into the bed of the truck and that's all we know. While the guy in the Ranger acted recklessly the biker also went overboard with his action hero impersonation.