I suppose the difference is that Android still tries to be a PC-on-a-Phone where iOS never intended to be that way. It's sort-of a Hardware+Software vs. Appliance nuance, while one is the other, the latter is not designed to become the former.
I think that hits the nail on the head. Android is the natural extension of Palm and Windows Mobile into the 21st century, a modern take on the classical smartphones. iOS is actually working backwards, starting from a "no you can't" and slowly working into a "okay I guess if you want to" as they add file management and styluses and official external keyboards.
It's probably also why people that do not (want to) make that distinction are rather polarized about their device of choice.
Considering phones now have pretty capable CPUs and 6Gb RAM turning a phone into a mini laptop is becoming quite viable.
I don't think that the concept of a phone-trying-to-be-a-PC is limited by what CPU or RAM it has. You can run complete Linux and Windows CE desktops on devices with way less resources. Doesn't mean that it's the UX the world needs ;-) On the other hand, as long as you know what you want, and know what is available, then none of it really needs to be in competition.
Not from a UX point of view. Many non technical people enjoy iOS exactly because you can't too much with it. It reduces complexity.