Perun shouldn't care about insights of configuration systems like registry or /etc tree, but Perun should care how his operating system behaves. Windows becomes sluggish over time, especially for end-users that like to install new software / games. MacOSX doesn't. That's the end-user experience.
So there's pro-Mac argument that you should listen to. I can also try to debunk other myths if you have any. Just to be on the clear side, i hate Microsoft and i don't like Apple much, either. Former crippled computer industry permanently, latter is trying to make fashion out of it. But i am also objective in this discussion.
You probably don't want to understand, but i'll try explaining anyway. There's MacOS and there's MacOSX. MacOS is old Apple operating system, alike Windows 95, operating system on Commodore Amiga and such. Steve Jobs left Apple and created a company called NeXT, to produce high-end computers. First web server, first web page ever served ran on NeXTcube (one of their models). UNIX is a type of operating system created in the seventies to power first computer networks and to fulfill the needs of multitasking and multiuser computing (and that same multitasking and multiuser was advertised as one of the strengths of Windows XP in 2001, seventies-legacy technology...). BSD is one type of UNIX created on Berkeley University (Berkeley Software Distribution). Mach is the type of operating system kernel (the main core of the system) designed in mind of controlling many different, but still critical tasks. In layman's terms, it was designed to be ultra-responsive.
BSD UNIX is a rock solid operating system marvel which basically invented the implementation of Internet, invented the critical data-serving operations, and still powers the Internet today and pushes the limits. So Steve Jobs' NeXT system blended BSD and Mach, to achieve ultimate stability and responsiveness. He succeeded.
Years after, he returned basically to save Apple. They used old MacOS graphical user interface with the NeXT system core to create MacOSX. Therefore, MacOSX is your friendly fancy Apple MacOS shell with one hell of a kernel beneath it.