So what was the bottom line on this story.
There isn't one.
In theory, you could buy a bargain basement sporting rifle and a top tier custom and shoot them both with the same ammo for comparison.
If they were clamped in a vice and all external variables removed there is a possibility that the cheap rifle could out-shoot the super expensive custom one.
However, this is incredibly unlikely as the former could probably be churned out and assembled in less than a day whereas the latter will have been checked (you would hope!) at every stage for faults in the materials, component tolerance and test fired after finally assembly (all of which takes a long time, adding to cost).
Going back to the point about 'the same ammo', you could argue that this is too big a variable and ultimate accuracy can only be found through extensive load development for that particular rifle. Taking load development to such an extreme that every single variable and combination is explored will probably wear the barrel out (shooting a single 3 shot group is not doing it properly) so it is better to start in the ballpark and call it a day once the goal (hopefully realistic) has been achieved.
I would argue that a sporting rifle does not
need to be sub MOA. Of course we all want them to be but more often than not I would wager that:
1- Most shooters are not good enough to hold (not shoot) the rifle steadier than 1 MOA, especially at distance. Can you keep the crosshairs within a one inch circle at 100 yards freehand, without a bipod and rear bag/support?
I can't but then again I don't claim to be good.
2- If you are deer stalking and need a follow-up shot, it is highly unlikely that the deer is going to be standing stone still in the same place as when the first shot was fired (like a target) unless you missed completely with the first shot, and that is your fault.
So, no point really.