But instructions are given by superiors, while code reviews (generally) by peers. If someone you don't respect starts barking "Change 'this' to 'that'", would you?

I mean sure, in some cases you can completely disassociate from the human side of code, disregard a comment's name in favor of objective truth or however you want to word it, but in a lot of instances you still have to share the same office with that person.