the reason a seatbelt isn’t “on you” to die, is after a collision it still helps everyone else for the driver to be conscious and still in the driver’s seat, to like steer and hit the brakes….
the car still moves immediately after a collision, it’s best if the driver hits the brakes, puts it in park and turns the engine off.

“Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety” ~ Benjamin Franklin