Microsoft also have a Windows 10 Mobile feature called “Continuum” that lets you connect a phone to a monitor, mouse and keyboard, and use it as a Windows desktop.
Why have they not noticed how these ideas can be combined, and why are they killing off the platform?
The problem is, they've strung along their mobile platform for years while trying to do all this, and left everyone on it without a paddle. With no devices and no point where they can conclusively say they're ready to try again, it makes sense for them to "kill it". And then launch as a new thing as some indeterminate point in the future where they actually have a product together.
As long as the Windows desktop (and particularly, Windows 10 S) development continues to push UWP, adding mobile support again later won't be particularly difficult.
Also i think Intel is still holding a handle on the x86 patent thing when it comes to emulating x86 on arm.
Its really sad that the whole UWP app development stuff didn't went so well. Technically Xaml and C# are awesome, there was (is?) also a react native uwp implementation.