Even that is not enough. The raw power advantage of the PC will probably continue for some time. There is no way to cram the amount of CPU/GPU power plus RAM/st

Even that is not enough. The raw power advantage of the PC will probably continue for some time. There is no way to cram the amount of CPU/GPU power plus RAM/storage capacity that exists in a PC into a slate style device, whether smartphone or tablet sized. That power may not be useful to a great majority of the population, but it is useful to some. And it will probably be decades before that power differential stops being relevant. Though it's hard to imagine how increases in the power of small form factor, low power devices won't also translate into even greater increases in the power of larger form factor, higher power devices.