Here's my view. The most important thing is which "industry" you are involved with. I am an engineer by day, and tinker with electronics and computer hardware / software by night. Windows dominates the engineering world in the same way that Mac dominates the visual arts. If you are not tied to an industry in this way, your choices open up.
I also think that the OS doesn't matter very much any more. My interaction with the OS is minimal. I use it for arranging files, choosing which program to start, and copying stuff from one document to another. Of course the application software interacts with the OS, but that's invisible to me, may even be fairly consistent between platforms. As I type this, Mozilla Firefox is occupying my entire screen. That's the "platform" I am using right now.
For general-purpose software, I use a couple programs that I bought long ago (Office 97 and Visual Basic 5), but otherwise, it's all free stuff that runs on multiple platforms. As for presentations, I have to admit that I agree with Edward Tufte:
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Most presentations aren't worth presenting.

But they can be shared as PDF's.
For hardware / software design, I am committed to Windows. I did that stuff on the Mac in the 90's, and it was an unpleasant chore. Besides, I don't know any Mac users who care about DIY hardware, so it just doesn't matter.
About reliability, I think it is difficult to gauge because it depends so much on the environment. A recording studio is a tame environment compared to a multi billion dollar company with centrally managed computers and large scale back office software running off a server in another state. Also, some people have more difficulty with computers, and complain more. In the 90's, the guy who tried to fix my Mac from crashing every 10 minutes said to me: "Think how much worse it would be if we were running Windows."