They explicitly stated that since June 18th.
This week, Xbox announced it is actively building its next-generation lineup across console, handheld, PC, cloud, and accessories. Find out more inside.
news.xbox.com
Xbox Ally is just a stop gap measure, only the next gen hardware used for windows handhelds will have Xbox Console library BC and compatibility.
An "Xbox PC" is a PC running on Xbox designed AMD APUs with Xbox console library BC. They have started using "Xbox on PC" branding for the Xbox app on PCs. To differentiate the software side from the hardware.
Non AMD APU PCs from other vendors will be status quo mostly. They could get the Xbox full screen experience but will have to rely on Play Anywhere for Xbox ecosystem. It's the "Xbox PCs" that will have the unique converged Windows and Xbox OS. It's a hardware based universal Xbox platform.
A Console will still act as a console, and likely no Desktop Mode or File System Access, and probably cheaper than Xbox PCs.
MS and OEMs are doing a family of devices in 5 form factors at least:
Xbox PCs
Xbox Laptops
Xbox Consoles
Xbox Handhelds
Xbox Cloud
All devices are meant to run the AMD APUs and have third party store access along with Console library BC/compatibility. That is what will separate them from regular PCs. It's an entirely new subset of PCs.