But people make technical design decisions in operating systems based on trying to make the operating system as conceptually simple as possible, which is what h

But people make technical design decisions in operating systems based on trying to make the operating system as conceptually simple as possible, which is what he means by beautiful, which I hope you would know from reading the literature. I would relish this essay question - I would have written about the history of Unix, the evolution towards Plan 9 and why it failed. These are important issues in CS, and if you are ignorant of them you are likely to repeat them. Your professor is testing that you have understood these lessons from history. I think you need to retract your implication that it's somehow an inherently bad or embarrassing choice for a question. All you have left is that you are fundamentally opposed to any philosophical, historical or human factor thinking in CS, and I don't think that's a supportable position.