A 2MOA gun shoots an 8" circle at 400m. Most hunters in American won't shoot that far for a number of reasons:
1) they know they aren't that good. They haven't practiced, their holdover estimation is weak, and they just don't have anyplace to do it. 400m ranges are the exception, not the norm.
2) They hunt where a 400m shot is rare. Most woodland or broken terrrain hunters won't even see game that far. They have to be glassing or scoping right there to do it, many don't. They just eyeball the terrain and try to stay awake.
Ethical shots are important, but the hunting community as a whole disagrees on what that is. Head shots are low percentage - it's a smaller target that moves more frequently. Only the brain shot or artery is a definite kill, any deviation only wounds the animal. Shooting for the heart-lung is much more sure in getting major blood vessels, and it's a larger, more stationary target. There's a more likely chance of breaking the leg or shoulder, jaw shooting a deer isn't going to recover it. You might find it later after the coyotes drag it down from starvation.
You don't need a MOA gun, you do need to know what is a good shot, and if you and the gun together can do it.
Most of the rest of accuracy in hunting is marketing. If you are hunting antelope or prairie dog, it's necessary. Whitetail deer near croplands, in the rut, not so much. It's more of a bragging rights exercise. Even the most accurate rifle is useless when no deer is dragged out of the woods. Hunters have done just fine with 200m lever actions. Shooters aren't made hunters because they have a scoped bolt action capable of shooting the wings off a fly. It's just ad copy.
If I could have a infra red scanner tethered on a balloon at 1000 feet, I'd be happy with iron sights. Just knowing where the game is and moving would be a huge advantage. After that, I'll take my chances. I still have to see them, and it's not all that even. But at least I would know I had my chance.
Does anyone have the cheat code for mapping a deer in real time? I'll take 50 yards and down as an ethical kill any day.