A few thing people should know.
MR without the spatial mapping (environment scanning) is practically a VR.
Even if MR uses the same spatial mapping AR use, their usage is still different. With mapping, you can render 3d tables, avatars or cylinders as placeholders for real tables, real people or cans. It is still dangerous for user to really run around and interact with objects or environments (unless we can truly map and render objects 1:1 scale).
* right now, WMR functions pretty much the same as Vive or Oculus without the spatial mapping. The differences… WMR doesn't need the external camera setup and you can flip the eye piece up with those WMR headsets.
For gaming @ home. VR has various physical limitations, that is why devs can only deliver floor-moves-you-don't-move, the arcade style rail shooter game or racer (is still a on-rail typpa game).
For non-gaming @ home. AR has a better future than MR, MR has a better future than VR.
In the arcade... none can really work without a companion standing right next to the device. Maintenance and explanation is one thing, hygiene is another. You need someone hand the hygiene mask to customers. And if you start assigning people standing next to those headsets... it's an amusement park setup.
In a meeting room (virtual team is getting popular nowadays, holoportation could be useful) or a product demonstration spot, all 3 typpa headsets are fine if you don't really move around. But if you wan to interact with other people... AR is the better choice. e.g. sales and customers can walk around the product freely and they can all interact with the product at the same time in the same space, and they can see each other, you can write some note, walk away, grab a drink and come back.
In the construction site... say we mapped a virtual structure onto the site 1:1 scale, and we'd like to offer a tour to our clients, would you prefer a transparent visor or you'd prefer to put a monitor in front of your eyes?Despite that we can totally render objects to cover all your vision, a transparent visor, is still transparent. One thing VR/MR does better than AR is that you can shut yourself away from the real world.
Answer: Yes, Hololens's FOV is not a problem to programmers. We don't need to re-code anything if future Hololens suddenly offers wider FOV.