This is really the crux of it. The counterargument essentially seems to be that such broad abstractions are fine in the small or when you have enough hardware,

This is really the crux of it. The counterargument essentially seems to be that such broad abstractions are fine in the small or when you have enough hardware, however that in no way carries over to smartphones where you want to do the most with the least, and even where you have a kick-ass processor and multi-GB RAM, you still want to reserve battery. The primary reason Android seems to need so much more hardware than iOS can be attributed to this. Even when you have powerful hardware, this can kill you in the large (which was the original failure of Windows Vista -- people forget that Microsoft did a complete revert after thousands of man years of work)