The recruiter misunderstood the answers and or he is not qualified to ask those questions. Usually when you ask someone something that is not literal as in "what is 1+1?" You can't expect them to be literal. Questions like: Why Quicksort is the best sorting method? Guy gave very good answer showing that he has perspective and he is able to make a valid argument. The recruiter on the other hand just read the paper and completely disregarded the fact that the person he is trying to recruit is a valid candidate.

Also at the end the recruiters attitude aweful. Like what is that, he was reading answers from a paper, couldn't make valid arguments back to the candidate and at the end turns and says to the candidate "sorry my paper says you don't know this and that, and goodbye?"

No, I meant that the interviewee misunderstood the questions/answers given by the recruiter and thus misrepresented them when he wrote the blogpost. Since he couldn't even get the questions right I highly doubt that he gave a correct representation of the recruiters attitude as well.

Which of the following seems more likely?

A recruiter who was already giving the guy the wrong interview, and whose job revolves essentially around HR and sales, made mistakes in asking a series of technical questions.

An expert with decades of relevant technical experience misunderstands and confuses basic networking and system topics.

Which of the following seems more likely?

A person fails to read a question verbatim.

A person who has been the "smartest person in the room" for decades has an inflated view of his fluency on a topic and makes mistakes in his favor when he tries to reconstruct the questions from memory.

That's a big claim. Can you share some of the actual wording of the questions?

If you work at Google you can find them by searching for it.

Maybe not such a good idea to post an internal link? :)

Do you have proof of this?