Recall when Microsoft was lagging far behind the other cool instant messenger kids, and was loudly crying for open interoperability and cooperation. Once MSN Messenger had a foothold, it slammed shut and their noble goals dissolved. Microsoft is certainly not alone in this self-serving morality -- it is a logical position -- but they do have a lot of examples in their corporate history.
Apparently the Microsoft employees are out in force today. It's also interesting how making an observation like this -- that the Windows app store is a failure -- leads people to pigeonhole. As I sit here on my Lenova 720 in Windows 10 Pro cross compiling an app between Windows and Linux in the WSL...hurrrRRRRrrr)