Well, if you want a mass market device that runs Linux, you have to meet the market. Otherwise we can start tracking 2525 as the year of Linux on the smartphone. If man is still alive.
I think "linux smartphone" would end up looking very similar -- some UI on top of a kernel with a very non-LSB userspace; therefore the concept is really not all that compelling
But take that far enough and you get Stallman'd into a corner where someone points out that's great, but no phone for you.