I hit a doe going 65 mph with an old Toyota (1990). Hit her square and barely felt a bump inside the truck. She slid down the road about 100 yards after hitting her. The truck is designed to collapse and absorb the impact. It folded like an accordion and protected the occupants as designed. The body shop just put a new front end on the truck by drilling out the spotwelds and removing the old one, slid a new one on, weld in place. Simplified overview.
A bumper that doesn't give may bend the frame instead if impact is great enough.
