It kind of made sense at the time, given the popularity of the Surface. The trend certainly seemed to be towards smaller form-factor, lower-power devices that sat nicely on the spectrum between a tablet and laptop.
Of course, that didn't mean they needed to completely overhaul the desktop experience though.
This is the sort of wisdom that leads a company to create macOS, iOS, iPadOS, watchOS, and tvOS. The recognition that some things are too dissimilar to ship in the same box.
Meh. I still think that is a mistake. Windows Mobile lost because it was late to market, and was not designed well the first two times.
Windows Mobile 10 was good, so was ability to develop for desktop, mobile and Xbox with one codebase. IMO Microsoft shut it down when it actually was becoming awesome.
Maybe Windows 10 ARM64 will still come back to phones though.
Of course, that didn't mean they needed to completely overhaul the desktop experience though.