You dont need an expensive scope to shoot MOA. Most of my fathers basic hunting rifles with sub$ 500 dollar scopes mounted will shoot MOA or under with 3 shot hunting groups.
I think more often then not, if a semi auto ain't accurate, it isnt because it has a cheap barrel. I've seen $400 savage bolt rifles group MOA and how much would their barrel cost ? lol like mentioned its probably going to be its design that causes the inaccuracy.
Pretty sure you could press a $3000 barrel into a Type 81 SA, mount a 25 power nightforce optic, feed it Hornady SST ammo and have Quigley down under pull the trigger and it would STILL SHOOT 5 MOA lol
Try using your fathers basic hunting rifle with a cheap scope at 300+ yards. That's where the glass shows you what is junk and what is quality. As the distance increases you'll also find that your 1ish MOA hunting rifle group opens up and is not as good as you thought it was.
I used to own a Bushnell Elite 6500 2.5-16 and at 500 yards I could barely make out the target, it was very hard to use, then I looked through a Sightron set to the same magnification as the Bushnell and the image was crisp and clean, I could clearly make out the target.
So yes, if you only shoot at 100 or 200 yards you can get by with a cheap scope. Since these are not precision rifles, if I had one I wouldn't bother with an expensive scope either. But then again I wouldn't be shooting a rifle like this off a bench all day just expecting/trying to make small groups.
Your comparison to a Type-81 is ridiculous, the T-81 (I own one) is a cheap piece of crap that looks cool and got the $1000 price tag because it kinda looks like an AK and came in non restricted (drives up demand and in turn the price). It's not a good design if accuracy is your goal. It was designed and built to be cheap and reliable and it did meet those requirements but it's a bullet hose, I doubt you could do anything to it that would get it down to 2 MOA.
A cheap Savage bolt action still has a much better barrel than most semis and will outshoot our factory semis because the bolt action has a simple, and rigid design and a cheap to manufacture action and stock which lets them use better barrel blanks and also manufacture the barrels to much better quality (better steel and button rifling).
Savage also sells probably 100,000 times as many rifles as most black rifles, especially what we get here as non restricted models. Why do you think an AR-15 is so cheap compared to most other black rifles? It's the volume of sales that lets them sell for less and still make money.