hexerik wrote:
... I want to be root on my system.
I completely understand, I and agree with you. Like it or not, Apple does not agree with you.
Look at it this way: It's not your Mac. It's theirs. Apple just lets you use it. Of course that statement is not literally true, but it is how Apple designs their products.
What is literally true is that's what Apple's market has grown to demand. Literally. The overwhelming majority of Mac users just want them to work. They can't be bothered with knowing how, or why, or who's responsible. A disturbing number of Mac users don't even know Apple, Microsoft, Adobe, Google, Facebook et all are all separate companies with separate business plans with separate and generally conflicting goals for separating consumers and their money. Literally. They don't know. Often they don't even care. I have had those conversations, much to my horror.
The manifestation of that ignorance is that Apple designed their system—meaning, their proprietary hardware and equally proprietary software, taken as a whole—to be as completely bulletproof as practicable. That's what they accomplished. Apple makes the whole widget, but if you want to modify it you certainly can. However, that product would no longer reasonably be called a Mac. The resulting product would be a Hackintosh, or a Frankenmac, or whatever. We are absolutely, positively prohibited from discussing such things on this site.
As for me I'm perfectly ok with running Ubuntu Linux in a virtual machine, and Apple is just as ok with it. I can do with it as I please. If I do something dumb the damage is limited to the VM. You can easily install a custom bootloader so that a Mac boots Linux natively, if that's what you want to do. Of course there are much easier and cheaper ways of doing that.