Microsoft doesn't want to be Microsoft anymore; it wants to be Oracle and IBM and primarily make money off of business consulting and the cloud.
I think Windows will eventually become a presentation and slowly-phased-out compatibility layer on top of Linux, similar to the way macOS became Unix, but even less different than its underlying OS.
However, it should be noted that I'm not very good at predicting things.
I think this is unlikely. In many ways the NT kernel is superior to the Linux kernel. I just wish it were open source and didn't have the rest of windows around it.
The Linux kernel is ubiquitous and free-as-in-beer, so it might win out. Android has already shown how you can build a proprietary userland on top of it.
Good point.
Wine is 26 years old.
Depends on what you mean by "good enough". Wine is an incredible project that has achieved amazing successes, but it still falls short in a lot of ways.
I personally don't use Wine but I've encountered people online in the last 10+ years that use the argument that it's "good enough" for people to fully switch to Linux. Realistically, I don't think Wine actually convinced more than a handful of users to abandon Windows