My main desktop is an old 2008 Mac Pro tower that is still going strong. However I've recently been developing on an old(5+ year out of warranty corporate) Dell desktop and laptop running Mint. Because it basically supports nothing I use on my desktop, it's completely distraction free. When I want a gaming experience, I jump on my Windows rig. I agree on all your points though, the MacOS environment is what Linux desktop wishes, and should be. It won't ever reach that level. Until Apple figures out what they ultimately want to do with professionals, I'll continue using 5-10+ year old hardware until it just dies.