At this point, I'm just hedging my bets: Windows for creative stuff; Linux for development; still using iOS for my phone (maybe the Pixel 2 will finally convert me to Android).

I don't find that Mac OS X (sorry, macOS) or iOS "just work" as much as they used to, so that's not really a requirement going forward. The platforms to which I migrate just need to be heading the right direction (which is to say, the opposite direction of Apple).

Microsoft is looking like a newly reawakened company. Between the Surface Studio announcement and the Connect() conference, it seems that Microsoft is serious about pursuing both developers and creative types (I'm in both camps, and Apple is underwhelming me in both areas).

Right now, I'm using Windows and Linux to get work done, but Microsoft's efforts at improving the Linux development story might eventually let me boot just one OS again.