I definitely agree that MS made some bad decisions that annoyed a lot of their customers, and that may have pushed a few of them away, but let's be honest here: we still haven't seen any significant shift away from Windows in the desktop numbers. Microsoft Windows still dominates at 96%, Mac is an also-ran, hanging in their at ~3% or so, and Linux trails at 1%, like it always has, with even that spread across several popular distros, and dozens of less popular ones.
For gaming, you're seeing more support for Mac and Linux because the major engines support those platforms, and so it makes sense to release for all platforms possible. That's definitely the good news. I think many game developers (including myself) would LIKE to see Linux doing better as a hedge against MS, so go out of their way to support it when feasible.
If you're waiting for MS to die, though, it's going to be a long wait. They've wisely started focusing on things like cloud services, Xbox, new high-end hardware, and so on, and of course, they still completely dominate in the business world (for PCs and productivity software). They've also got a lot of cash reserves. They're no longer the dominant player in the industry like before, but they're hardly becoming irrelevant.
TL;DR: Wake me when Linux on the desktop breaks 1%.