I don't see why the driver should have shot the violent man. The driver was safe in the car and could drive away. However, it would probably be comforting to have a gun if you can't get away.
The smart thing to do is avoid violent areas altogether.
He was trying to drive away. He kept getting blocked and smashed more. Safe in the car? That car wasn't much more substantial than a smart car and windows were bashed completely out. That wild nigger could have entered the vehicle, jerked somebody out of the vehicle, or struck somebody in the vehicle. So you would have been willing to bet your life--your family's lives--those things couldn't/wouldn't happen? That that erratic animal wouldn't pull a knife or gun in a flash? All the while he's smashing away, spraying glass into the car, and putting occupants at risk of being struck either intentionally or wantonly by glass of his club.
You do realize that the manner in which he was using and brandishing his club that it constituted a deadly weapon/dangerous instrument, don't you? Do you have any idea how the human skull compares to car glass? I would dare say that a front windshield is stronger than the human skull.
Any occupants of that vehicle were in serious danger. I would have wasted the mangy varmint--it would have been CLEAR self-defense and I wouldn't have missed a wink of sleep over it.
Avoid violent areas? That's a possible fix to some extent. I didn't see enough to say for sure, but maybe that ape had roamed out of the jungle. Cars appeared quite modest but not junkers.