Bumpers from the 80s and early 90s were more substantial and outset from the vehicle. If a 5mph impact did anything to the bumper, it took the hit and the rest of the car was generally fine. The bumper was easy enough to replace because it was external to the vehicle.
Modern cars don't have external bumpers and what you see on the outside of the car is a "bumper cover". The actual bumper is under that and no longer spans the whole front/rear of the car to the sides. Many new front bumpers don't go past the headlights.
So in a 5mph crash in a modern car, the bumper cover (made of plastic and held on by plastic) takes the impact and generally gets destroyed. Replacing it costs several hundred dollars in parts before paint (because they're all painted). There's also more labor involved in replacing it because it's so integrated to the car. Bumper covers now clip into both fenders, core support, and undercladding and removal means working with all of those parts, then lining up body lines after.
I think it's less a comment about serious accidents and more a comment on getting rear ended at a stop light now costing $600+ in repairs even if your airbags didn't pop.
And cars from the 30's-50's were often tank-like by comparison. You get into a high-speed accident in one of those and they would just shovel out the raspberry jam you turned into, hose down the inside, tug on the frame a little to line everything back up and put it back out on the lot.
Modern cars don't have external bumpers and what you see on the outside of the car is a "bumper cover". The actual bumper is under that and no longer spans the whole front/rear of the car to the sides. Many new front bumpers don't go past the headlights.
So in a 5mph crash in a modern car, the bumper cover (made of plastic and held on by plastic) takes the impact and generally gets destroyed. Replacing it costs several hundred dollars in parts before paint (because they're all painted). There's also more labor involved in replacing it because it's so integrated to the car. Bumper covers now clip into both fenders, core support, and undercladding and removal means working with all of those parts, then lining up body lines after.
I think it's less a comment about serious accidents and more a comment on getting rear ended at a stop light now costing $600+ in repairs even if your airbags didn't pop.