"Right now Microsoft is the only option for affordable really high-end desktop/laptop computers."

I have a high end laptop that doesn't run Windows as the primary OS. (I occasionally run Windows in VMs to verify that cross platform OSS software runs on it and on Patch Tuesday to fix the latest exploits...) Other than that, Linux is my primary personal machine at home for development, research, office work, music and movies, etc... I'm also shopping for a new desktop and home media server that will probably not be Windows.

Windows currently has a chokehold on the desktop market with it's huge ecosystem of applications and entertainment, that's what's preventing many folks from moving. Games and accounting applications are the only reasons that my spouse still runs Windows at home.