IF they choose Windows, it's because they want compatibility with software they already use. That's what doomed RT. Microsoft thinks Metro/Modern/Market apps are what Windows is now. They want to shed the past. But customers buy Windows exactly because of continuity with the past.
Android customers want Google's ecosystem and the big selection of apps in the Play store. Microsoft's other problem is that the Bing/Live ecosystem isn't competitive.
I agree with the article to the extent that Microsoft should have done what Windows customers wanted: Let Windows be Windows. And they should have freed themselves to build the future, initially as a companion device to Windows. Or they could have bought Blackberry, or not shut down Nokia's OSs and gotten a leg up on that transition. QNX running and Android-ish userland based on an MSIL VM would have kicked ass. Instead we are dragging Windows everwhere and the userland is a hodgepodge of Web, C++, and MSIL apps.
Killing RT and running real Windows everywhere is a small improvement over the current mess, but Microsoft is wading deeper into the swamp instead of finding a way out. The only way to win at mobile is to make a non-Windows product. They are so far away from that as to be a lost cause, even if the next CEO sees the problem.
Windows 8 has the advantage of being more consistent across different devices, and gives a polished experience. This makes the product easier to market as the user can make assumptions about what they will get (unlike some crappy Android builds).
If you assume that most users don't care about the inner workings of the OS the real issue with WP8 is poor app quality.