Having nearly any kind of collision while riding a motorbike is not a minor thing.
Especially if it perceived to be (and in this case, it was by both the rider and more than one observer) intentional, that is basically assault with a deadly weapon, the weapon being a 2000 lb. automobile. (and yes, when a car is used as a weapon to collide with or run someone over, it is considered “assault with a deadly weapon”. In real legal terms everywhere, that is true to my knowledge)
If the guy reacted with hot blood to an intentional collision which can result in death or severe injury to the rider of a motorcycle (even at very low speeds) I cannot say I can blame him.
He was certainly within his rights to follow her to wherever she was going, even if he did have the alternative of reading the plate and reporting it.
How does he know the car is hers, that it isn’t stolen, that she isn’t an illegal who will disappear, etc? He doesn’t, just like if she was two months pregnant, he wouldn’t know that she is pregnant either.
I think we can all agree there was enough hot blood and stupidity to go around, and that she should have considered all that as he should have as well. But she paid the price for it.
The hit and run suspect only paid the price, when she decided to take a gun into the street and attempt to kill someone.
There is really not much to discuss here.