I was (and still am) a big fan of the WinRT-equipped Surface devices. The desktop was actually a GOOD thing about it. What hurt the Surface RT/2 was (1) the price and (2) the name. Microsoft named the two devices (non-Pro and Pro) and their operating systems too similarly which caused confusion. Call the Surface RT the "Zune tablet" running the Zune OS that happens to run apps in the app store, and the perception and reception would've been different.
Speaking strictly from a touch, tablet perspective, except for the active digitizer, there was no difference between the Surface RT and Pro... except that the Surface RT had longer battery life, was lighter, ran cooler, and didn't have a fan. Windows tablets will sink or swim as tablets primarily on the quality of the apps in the app store.
So even the Surface Pro 4 and Surface Book will have their tablet experience limited by the touch-optimized apps in the app store.
Except the desktop was not a touch optimized experience (which you say lives and dies on the App Store providing those experiences), and couldn't be extended on RT devices, because those devices ran ARM instead of x86, so no Photoshop. Thus, they didn't sell when you could get x86 and actually make use of the desktop and ignore the fact that the Store wasn't actually up to snuff.
@JPIndustrie is spot on. That is EXACTLY what Microsoft is doing. This is one of the reasons why Microsoft NEVER advertises any of the Surface devices WITHOUT a TypeCover. Microsoft knows that Surface devices are primarily notebooks and only a tablet "in a pinch".
Except my argument is that they aren't pushing people back to the desk, but responding to the fact the developers largely ignored the Store for touch-first apps, and users were buying x86 Win tablets over ARM ones. So they are basically creating the device for today, not what they think is coming tomorrow.