Correct, not one right assertion. An AR15 is a low powered weapon, does not hold more rounds than any other magazine fed rifle has half the range and stopping power of a classic 30-06.
I have a magazine I got a while back that isn’t much larger than a regular 30 rounder and holds 60 rounds (Surefire Mag)...not a drum canister, just a thicker regular mag. You won’t get this in a deer rifle model.
I fully support 2nd Amendment rights. But playing Devil's Advocate for a moment, critics will seize on the perp's 100-round magazine for the AR to support their gun-grab argument. I own a shotgun and several rifles but have been away from active shooting sports for some years. Are magazines of that capacity available for magazine-fed semi-auto sporting rifles? I simply don't know but rather doubt it.