Because Apple built it's brand around control. If you think windows locks down their users, try working on a Mac. Shit, you couldn't set a wallpaper on an iphone for 3 years. It's about the ability to make things work the way that you need them to. Maybe Linux is better there, but Windows vs. Linux is going down a mountain road with or without guardrails. You'll get to the bottom either way, but one might be a bit more hazardous.