As for whether operating systems are necessary, by most common definitions (being, as I understand it, a set of software that defines a common base of abstractions over hardware, so as to allow multiple other pieces of software to access said hardware at a higher level of abstraction), yes, they are, if you don't want to go mad. But I get the feeling that isn't what you meant...
In short, I can respect your opinions, but I do not agree with all of them. Much of this derives from the mindset that tinkering with even the most important things, regardless of skill, is important to learning. If that makes me stupid, so be it.