I'm kind of a power user too.
I've built my first and main computer a year ago (still my actual rig) with macOS, Windows and Linux.
Primary reason is that I can have a system with
my chosen hardware, not outdated GPU's, processors, platforms etc and a way more powerful system for way less money. I really hate the direction Apple is taking, which is "
SOLDER EVERYTHING INTO THE BOARD SO NO ONE CAN UPGRADE AND THEY'RE FORCED TO BUY NEW STUFF! MEANS MUCH MORE MONEY!!!"
I also really prefer macOS over Windows for about everything, use macOS it as a daily driver with my MacBook Pro, and love to tinker and learn at the same time. Because I started using Logic Pro X on my 2012 MBP, I kind of had to use macOS to continue my work. Also, Apple's system works very well with Adobe's CC Suite, Blender (3D free software), of course Logic... Well, everything to actually "work and create". I do not get that "nice and working properly" under Windows. With the last (extremely sketchy) "Creators Update" and their 3D Paint, it makes me laugh how they want simple users to try stuff they will actually never use. Microsoft's OS is just not as nicely built as Apple's one.
I also use Linux to build and hack some Android stuff, like kernels and LineageOS etc. I use Windows only for gaming.
Oh and this Sunday I've installed my custom watercooling loop including the CPU and both GFX cards for some decent overclock
This Wednesday i'm rearranging all of my disks, because I've installed some M.2 SSD from Intel (600p Series), and my partition layout is kinda complicated.