Perhaps true for small caliber automatics, but most certainly *not* accurate to say when thinking in terms of bolt action rifles (or even lever-action weapons such as a Winchester 30-30).
As far as durability comparisons go try this with your Remington 700 or your granddads Winchester.
Pull one of them from underneath the rotting corpse of an enemy soldier who's been laying in a rice paddy for a few days. Hose it off with plain water and toss it in your locker for a month in the SE Asian jungle heat and humidity.
Take it to the range, kick the action open because it's rusted shut. Put 120 rounds through it.
Repeat the toss it in the locker part and the 120 rounds part (without cleaning) once a month or so for 11 months.
Then get back to me about it's 'durability'.
L