Microsoft could still open source some or all of the NT kernel and try to compete for mindset. It's still incredible how much work they put into porting the NT Kernel for some embedded scenarios (you can run it on a Raspberry Pi or things smaller than it) in the Windows 10 lifetime but couldn't seem to understand why more people weren't licensing it more when Linux is cheap as free for embedding. Even when Microsoft went to "free licenses" (still with too many caveats such as type and size of screen attached) the open source appeal was hard to get past.

I'm still somewhat surprised with all of Microsoft's cloud focus and how much of Windows is getting open sourced that the NT Kernel itself hasn't been a priority to win back embedded applications that Microsoft has lost to Linux especially. I certainly understand the massive sunk costs in the NT Kernel that some accountants would see it as too much very expensive proprietary R&D, but it's still interesting to imagine what would happen if Microsoft got over that hump, even if they kept the Win32 userspace and most of the rest of Windows proprietary.