Everybody went in for Windows as their favoutte desktop operating system a couple decades back. After XP, there is little to be gained from Microsoft's latter offerings in operating systems. So now we are seeing large migrations to Linux and larger numbers still sticking on with XP.
In the tablet marketplace, Microsoft is a recent entrant. iPad and Android tablets comfortably have more than 90% marketshare in this segment.
Microsoft started out with restrictions on what processor, screen size and memory can be offered by OEMs in tablet form factor, to try and prevent tablets eating away their desktop marketshare.
Then MS provided a convoluted method of delivering apps for tablet devices compared to desktop apps with similar functionality and architecture. Developers boycotted the entire Surface market as a result.
And the Surface is priced more than twice that of a laptop, despite the latter providing more usability and applications, once the OS is upgraded from 8 to 7. Yes, I meant upgraded, it wasn't a typo.
The moral of the story is You Cant Fool All The People All The Time, as Lincoln famously said. Remove the lock on the bootloader in all Surface tablet categories, Allow all Surfaces to connect to the Active Directory, Come up with more meaningful development tools and app for ARM Surface tablets, and lastly price it between $100 to $300 in varying configurations. People might be tempted to take notice.