I think Phil Spencer has been fairly clear about Scorpio though.
"With Scorpio you're introducing the idea of people playing online together and against each other in competitive multiplayer, one person perhaps on Scorpio and one on Xbox One. If the Scorpio enables such things as better framerate, won't that give the Scorpio user a competitive advantage in certain games?
Phil Spencer: Obviously the game designers of our games have to think about framerate and field of view when they're designing competitive situations. We have this scenario with cross-play today, people playing games on PC and console at the same time.
On a console to console experience, when we designed Scorpio and we said 4K console, we looked at games that are running at, let's say 1080p 60 on an Xbox One, and said we want that same game to be able to run at 4K 60 on a Scorpio. We looked at the design of the games we had on Xbox One today and said, if we increase the resolution and maintain the framerate we have, could we hit that?
I think framerate's more interesting than resolution in terms of competitive gaming, and we wanted to make sure teams were able to build the 4K version of their game at the same framerate they can hit, at whatever resolution: 900 or 1K or even 720 that they're hitting on this box. So, we thought specifically about that situation and talked to developers about it."
http://www.eurogamer.net/articles/2016-06-15-xbox-boss-phil-spencer-the-big-interview
So yeah while there is no mandate about resolution, you can make a 1080p Scorpio game for example, there does seem to be a mandate about keeping XB1 and Scorpio framerates similar
Im not even sure a developer would want to put in the extra work to make a Scorpio game run at 60 fps compared to 30 fps considering Scorpios install base will be minimal
There is no reason 720p can't become the default for X1 in a few years. DR3 at 720 was a better looking game to me than ANY launch game on PS4.
Alternatively, just turn off resource-hog options that add minimal image quality like shadows and AA. Both of those things make very little meaningful difference in image quality to me between none and best.