I think that AR will become as ubiquitous as our phones because all of the core functionality on a phone will be better on AR.
Instant alerts in my peripheral vision (again a non-obtrusive display is crucial)?
Call up directions while driving with cortana / siri and have lay over unobtrusively?
Watch TV on a 100" screen anywhere?
All things that I've done / played with in Hololens demos, all amazing, all "no question" will be massively adopted when they get the form factor correct.
Heck just look at a current app like SNAP - already on 50%+ of phones of 18-24 year olds - is a perfect app use case.
Camera, stories, sharing - all better and more accessible in AR.
And they're already demonstrating the desire / utility of AR via "filters" and their new "World Lenses" release today.
Want that bunny rabbit filter on all day as your "look"? Done.
Want it only accessible to your co-workers and not your boss, cool set it and forget it as long as the device knows your social graph.