I use Windows 10 but I am not a fan. I use it because of programs I need to run but I'm sure there's a MAC/Linux replacement or alternative for them I just don't want to buy a MAC, but I run Linux for my Crunchers and I'm quite tempted to test out a Linux gaming rig.
I wish I had stuck with Windows 7, for me it was one of the best Window's OS's as far as they go.. Sadly though with newer GPUs and such I went with 10 and to my disappointment it wasn't all that it was really cracked up to be for me. Still running 1803 on my gaming rig, it tried updating itself, crapped itself and then rolled back after an hour of my time went out the window...
If I really would like to run another OS, I will simply install it and run it. I've still got 98, XP Pro (32 and 64) and 7 64 Ultimate, for me, these were the best and with older hardware, I'd use this in a heart beat...