"If I had asked people what they wanted, they would have said faster horses."
People do not desire better desktop operating systems. They want computers to disappear. It simply does not matter how good this awesome new, secure, desktop OS is because it's built for a world that doesn't exist anymore.http://blogs.hbr.org/cs/2011/08/henry_ford_never_said_the_fa...
However, we still use horses as transport. Sure, it's often just for pleasure, but the Police still use them, and rural people still use them, or people in mountains etc, because in those situations they are still better than anything Ford came up with.
So I don't think that quote is relevant here. People have accepted 'post-pcs' into their lives and they are good at lots of things. There are things that larger 'real' computers are better at though, and I don't see any evidence that will change.
You say that nobody wants to use desktops and people want computers to disappear. Unlike you, I don't believe that already, so do you have some evidence for it?
Took my old brain a second or two to realize that I had previously heard that quote associated with Henry Ford.