Of course I’ve been at a job place after the interview. Do you think that because we disagree I must have zero experience? (Life Pro Tip: Two experienced, knowledgable, thoughtful people can sincerely disagree because they have different values, experiences, or knowledge. One of them can disagree with the other without belittling the other.)
The goal of a standard whiteboard coding interview is not to test on stuff that they cover in cs 101. It might presume knowledge of a *small subset* of basic computer science, but this is quite a small subset and rarely what distinguishes people — for good or bad.
The goal of standard whiteboard coding interviews is assess your ability to solve new problems that you haven’t seen before. That is absolutely relevant to work.