Speed flattens trajectory. But bullets don't kill. Speed doesn't kill. Guns don't kill. Shell casings and powder charges don't kill.
Bullet HOLES kill. This is the premise of the OPs post and he is 100% correct.

Many US Service men walk around alive today with metal in their bodies. I know from personal experience! Many of those metal pieces were put there at velocities well over that of rifle bullets, but if they hit someplace non-vital, they can be survived.

Bullet holes that penetrate vital places are what kills!