I have heard this several times over the years from those who were actually in the mess and the chips were down. I listened.
All systems have growing pains. To get current - talk to some sandbox vets. Different things from the VN era are their focus.
I quit counting shots while shooting 5.56mm in an AR at 250,000 rounds years ago. Two notable jams and they were ammo related. Three hang fires also ammo related. Two hardware failures, one extractor and one cracked gas block.
1. I always buy name brand guns and parts.
2. This wasn’t in combat.
3. My AR’s get cleaned and inspected to the max on a regular basis.
YMMV