Given the test shown in the video it appears that it is possible for those little 'leccy' motors to move an aircraft just on APU.
Jury is still out on wear and tear on the gear retraction and extension mechanisms but the economics of carrying the extra weight are pretty straight forward so if they don't add up companies wont buy them. If the economic stack up then they will.
Having used hydraulic blade fold I would stear clear of hydraulic motors in the wheels it will just end in tears.
All up though it is nice to see someone has thought laterally about a problem and come up with a workable solution.