I still suspect they were right that that was the plan, and only backlash from consumers/poor uptake of the Windows Store for games largely killed it off (Xbox Game Pass still uses the UWP-type approach).
I mean, it wouldn’t be the first, fifth, or even maybe tenth time Microsoft adopted an stance that was bizarre and seemed patently anti-consumer or even insane. I know some of us are big MS fans and I am admit I’m kind of one of them, but they’ve fucked up like this quite a number of times. I mean, spectacularly and memorably they did so repeatedly with the Xbox One in 2014, where they had not one, but at leas three different major points of contention where they flew the face of common sense and “how things worked” in order to try and convince people to adopt Brave New Standards, as it were. Some of them seem less extreme now, or even like okay-ish ideas, but they were bananas in 2013, and put in ways so rude and thoughtless that high-paid people ended having to resign and so on.