Although Microsoft has been very successful lately, I wish they hadn't given up on competing in some consumer areas such mobile. Now we are stuck with only Apple & Google.
I'm betting that Microsoft is going to come out with a Surface branded Android phone in the next 2-3 years, and allow Android apps to be entered into the Microsoft Store. Use their leverage in developer tools to make publishing in all 3 stores easy. The groundwork is being laid, but I think they are very much focused on the cloud and catching up to AWS offerings.
I think the new MS realigned with some of the old MS' ideas: the Surface line is meant to lead OEM hardware manufacturers, not to be the sole OEM hardware manufacturer. I don't see the new MS releasing a new phone/phone OS branch without phone hardware manufacturers begging for it. That doesn't seem likely without pressure from phone carriers, and they seem very happy with the Android and Google duopoly as it is easy for them to sell and/or profit from.
Hah, the Freudian slip there of "Android and Google" instead of "Apple and Google" amuses me noticing it days later. It's probably increasingly accurate, too.
I had a Windows Phone. I really liked it. What I didn't like is that there were no apps for it. So I ended up switching to an iPhone.
I also had a Windows RT tablet. It was pretty good, but I wish MS hadn't nerfed it. If I could have used a browser other than IE I would have likely bought another one when the SSD failed.
I wonder if they wait for the right moment (e.g. when Android gets replaced with whatever Google tries to replace it with) for a new play on mobile or if they really are "done" with it.
I think there is a still a possibility that Microsoft expects the phone and PC markets to merge and hopes to be there with welcoming arms when it does, but I'm getting the impression they won't build new hardware to do it if they can't convince other manufacturers to join in.