What a funny logic

IT IS all about how well a car survives in a crash, If the car didn't survive in a crash, what's your chance? How safe a car is determined, mainly but not all, by how much P it can take.

A car was totally destroyed during a crash, the driver stood up and walked away without injured. Who was he? Iron Man?

BTW you need to be reminded that conservation of momentum can apply in most collisions, it doesn't require a closed system unlike conservation of energy. Friction, for instance, always exists during collision but can be ignored, otherwise conservation of momentum should be removed from textbook because there is NO 'closed system' on our Earth!