I think the parent's comment is better phrased as "There's no constraint preventing iOS from being just another tablet OS." Apple consciously refuses to decoup

I think the parent's comment is better phrased as "There's no constraint preventing iOS from being just another tablet OS." Apple consciously refuses to decouple their hardware from their software (and I agree with you that the iOS experience is better than the Android one, although I don't think it's an objective truth). Comparing iOS adoption to Android adoption is not some universally indicative metric (I'll bet all the money in my pockets that many more iPad owners know what "iOS" means than Android tablets know what "Android" means, which is incredibly important when you're, say, trying to build an ecosystem) but it is still important (I'm a developer with limited time resources! Do I spend X hours building an Android port?)