Except that the patent sketches from Microsoft show individual panels brought together with an ingenious hinge design. Granted, the Andromeda Unicorn is/was supposed to be a pocket PC that can take phone calls while the others are just Android phones with silly putty screens. I believe Motorola is on the right path with the RAZR clamshell approach. My theory would be to put an external display for those times when you need to check a notification or take a call without having to open the phone. It would reduce the overall number of times you flex that screen.
Of course, Microsoft could just share (for a fee, naturally) that hinge tech since they’re never going to release the damned thing anyway.