The location of where you sit is sort of orthogonal to the device you can use. If say your smart phone was powerful enough to edit and compile files (I assume you are a developer) then just lay your smart phone down, let it wirelessly connect to your large screen TV and your keyboard, and now you can do the same thing your desktop does now without having a large motherboard, hard drives, loud fans etc.

You are basically arguing that keyboards and chairs are here to stay which I think short of a good mind-to-computer interface that is true. But just not sure about the current hardware and operating systems.