What are you talking about. Microsoft's strategy for the last few years is about cloud and serices. As part of this plan they finally have a winning mobile strategy, having their services available on the key platforms (Android and iOS). The success of the strategy has been demonstrated by Microsoft's financial results.
Who wants to be in the low margine mobile hardware and OS business. Not Microsoft, after losing billions in mobile they are finally being successful where it matters.
I was wondering about this a few days ago.
One thing that the tech companies all appear to be deathly afraid of, is giving up anything that they could possibly make money from. Look at apple with their new 'Apple Card', they're basically moving into banking. It makes complete sense why they have held NFC payment off their platform now.
So I sort of get the feeling that MS has learnt a huge lesson with google, who became huge by living off largely MS platform, back when it was just a website running on millions of windows machines.
There's no doubt that people at MS look at google and think, we were there, we could have easily done what they did. But since google have expanded into platforms, all in order to protect their premier product, at the time, I have a suspicion that maintaining a platform and all those costs associated are large and onerous. MS probably have strategically decided that they can leave all that work with google, and just make money offering their software on it.
That's probably what killed WP; I suspect that the strategy changed when an important metric showed that they could never make as much money with WP than doing what they're doing now. It possibly explains why they've decided to move edge onto the chromium engine.