Ok we'll "up gun" to a .22 airgun, or go hog wild & go for a .22RF. Now you have a .22 round hole in a paper target, & it still ain't a battle cartridge.
The absurdity was comparing paper to a living moving 3 dimensional object, not the minuscule difference it hole diameter.
Neither the air gun nor the rim fire are going to be putting holes in the X ring at 600 yards, beating out the Garands and M1A for scores either
But as for making it a "battle cartridge" the Soviets developed the 5.45x39 then stuck with it. The Chinese developed the 5.8x42 and stuck with it... That's 21 caliber and 23 caliber. The 5.56x45 must have something going for it if arguably the only rivals for "global superpower" status are adopting cartridges with similar performance.
Also, the 5.56x45 has outlasted the 30-06, 30-40, and 45-70 as a "battle cartridge" so there's that. One would think that such an inadequate "not a battle cartridge" round would have been dropped like that flash in the pan 30-06.
Of course I find it hilarious that half the criticisms against the 5.56 is that the M855 green tip just "pokes holes through people" and your criticism is that it just pokes holes in targets.
Of course to illustrate why your argument is absurd, why not give every Infantryman a 600 Nitro Express? If bigger is better clearly the 7.62 must be vastly inferior to a larger bore size. Unfortunately such an obvious "reducto ad absurdum" fallacy serves no purpose other than to show that caliber has little to do with suitability as a general purpose "battle cartridge" as you put it.
To further drive the hammer of reason down on your implied necessity for 7.62 to be a "battle cartridge", 300 Blackout fires 7.62 caliber bullets and is a horrible choice for a standard issue round, and the 30-30 is also a 7.62 caliber round is also a horrible choice for a general issue round. If this doesn't illustrate the point that "caliber" isn't the deciding factor on "effectiveness" I don't know what else to tell you.
Then again, you could volunteer to get shot with a 5.56x45 at 600 if you are so convinced that making holes in targets has no bearing on making holes in humans. If you are truly convinced of the soundness of your argument I truly look forward to seeing this on youtube, at least until it's pulled.
Jimro