Its been done, back when chink ammo was available I wore out a Maadi AK.
But it had issues.
The AR is even harder to wear out in many respects, the modularity it has allows easy parts swapping including barrels unlike the AK. And your average owner can do this themselves normally.
A friend in western Nebraska has a second year Colt AR, its on its third barrel and an unknown number of spring sets. I would hate to guess the number of prairie dogs and coyotes that have fallen to it, and a few other critters I’m sure.
It goes from pickup to tractor to combine and occasionally even gets cleaned.
He buys ammo by the case, says he doesn’t have time to reload for it.
The amount of junk I pulled out of it last time I was back there was amazing, wheat kernels, chaff, mud, rocks, if it could fit inside somewhere, it was in there.
I still don’t know how some of that junk got inside, its not an AK with openings for junk to get in.