You're right about the x86, but actually, the 'Continuum device' can do this. It allows you to connect the phone and display and use as a desktop. The device can also 'cast off to other displays too. When you un-hook your phone and re-connect it's like Kim Dotcom arranging his wardrobe. Whoppee!!
Another comment here says no RDP (I think). This IS actually available but again you need Terminal services and app services enabled in Azure with all sorts of jiggery-pokery to make it work. Even then it's like a TS-session from hell. And it not a no-cost option like it is for desktops, even connecting to a two-license standard server role in your tenant.
UWP apps are crap on a desktop format. Try moving them between displays and guess the resulting window size. There are also virtually no ent apps packaged as UWP apps.
Microsoft have not run out of ideas, however and this is exactly the problem. The question from BYOD-invaded MSFT-fan IT managers was "Could we have a WINDOWS phone?". They wanted one that would leverage the gzillions they've spent on AD, Azure and now O365.
No, they got a consumer device that, starved of any real sales has been floundering around in the darker corners of Phones4U ever since. And then to manage a fleet of mobiles with MSFT tech you need Exchange online with Activesync and probably intune.
Those same IT managers blinking in the sunlight have found that they've been sold a goofer. No-one in MSFT has the cahunas to own up to the fact that biz requirements came last and probably too late.
In the meantime, all the Windows infra bells and whistles continue to be added for the Android and iPhoney ecosystems whilst Rome burns.
Unless Windows Phone whatever anniversary edition is a 'seamless experience' at the back and front ends, expect the unhappy marriage to end in the divorce court.
Windows Phone remains a very expensive Microsoft Office Device for business.