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
Oh I understand, And I have owned a couple myself over the years, but these issues would not have happened with an SKS even as dirty as you can get it. Seriously, they are almost indestructible. They require no special tools, they can be field stripped and reassembled in 30 seconds which in realty almost never needs to be done unless it is to dump mud out of the rear cover.
And it is designed so that the only tool needed but not required to take it down is a round itself. Simple, basic, very few parts to break and they have one of the best bolt systems deigned. There may be some who don’t know this... But they have the same tipping/tilting bolt design as the FN/FAL.
If I am going to need to rely on a firearm in a true mess the last thing I want to worry about is broken parts or spending all my time cleaning it to make it work. And I want stripper feed which is not an option with AR and AK platforms. I like my old .303 British for the same reason, Stripper feed.