Honestly from a third-person perspective I can't see any reason why this wouldn't work. Maybe that it wasn't intended for the "second" screen to be touchscreen but I really doubt that Microsoft would code in that limitation, especially when manufactures were making Android phones that convert to
laptops and
tablets and such a concept could be a hit with Windows 10's Continuum. I don't know about driver issues, but the Surface RT used decent chips so Microsoft should be able to support it if they wanted to.
I'd like to believe that Microsoft is working on it, but it's a lower priority and they don't want to make promises. Plus they would be converting from a PC OS to a mobile OS, so there would probably be a lot of work to do to make the upgrade procedure stable. And there's still the whole deal about Office, as the mobile versions are not as feature-filled as the desktop version, even Office RT.