I used Linux for years at work for embedded development. At the time there was basically no better platform for what we were doing and I loved it despite its quirks. It's totally fine for a desktop OS unless you must have that platform-specific program. My next computer will likely be a Linux box.

For laptop I'm definitely MBP all the way. It's by no means perfect, and yes, Apple is trying pretty hard to sabotage it, but it's still the best laptop experience overall. For me MacOS feels like home, although I get if it doesn't for you. I don't use it to develop for iOS, I just like it. When I need to run not-MacOS I fire up a VM and life is good.

The Windows UX has been utter torture from day one and has marginally improved in the last few years. I feel about it the same way a lot of people feel about PHP: it's just a fractal of bad design. I can appreciate that it's the universal desktop OS and necessary if you need to run certain software. For instance, I'm going to have to spend some quality time with it in the not-too-distant future for work. But that's the only reason I ever touch it.

Mobile...eh. Yes, there's money developing for it, but eh. You want it, you can have it. There's more than enough money developing for other things, and there always will be.