Big difference in what a person wants, needs and can afford.

I have a close friend that has a $4000 rifle with a $3500 scope sitting on top of it.
The gun is in .300Mag. The total cost of my rig is $800. It is a 25.06. Dead deer know no difference in which one of us put a bullet through it's heart, lung, spine.

The reality is that most folks cannot afford a custom gun and all the bells and whistles that go with it.
The reality is, even if a person has a top of the line custom rig but cannot shoot worth a hoot, the capability of the gun/scope is of little value.

A consistent gun, consistent ammo, consistent shooter are all absolutely necessary for shooting accurately. It is a combination of factors, not just/only the custom built bolt gun, or the high quality optics on top.

There is also a BIG difference in a "hunting" rig and a "bench" rig.
Hunting:
4MOA at 100-150 yards is deadly - means all bullets within a 6" circle at 150 yards
3MOA at 200 yards is deadly - all of the bullets within a 6" circle at 200 yards
2MOA at 300 yards is deadly - all bullets within a 6" circle at 300 yards
(2MOA = 2" group at 100 yards will open up to 6" at 300 yards) (deadly in a hunting situation)
1.5MOA = 1.5" at 100 yards, 3" at 200 yards, 6" at 400 yards
In the real world of hunting, these accuracies are realistic and reasonable. There is little to no reason to expect accuracy above and beyond this. Accuracy beyond this is rare.

Bench shooting is a totally different world. Time, Energy and Money is dumped into the development of single load that performs in an EXCELLENT way in an individual gun. Massive amounts of time and energy go into developing shooting form that is flawless, reliable and consistent. Accuracy of this type is not necessary in the world of hunting.