Picking something counterintuitive as interview question is not a great idea. Defeats the purpose - harder to tell whether the candidate is going with conventional wisdom because that's what they think the answer is, or because the candidate thinks that's the answer the interviewer expects.
i.e. You could get sharp candidates that know the correct technical answer but intentionally give the wrong one because they rightly concluded statistically odds are the interviewer is on conventional wisdom wavelength.
Could be good if you're specifically looking for someone good at mindgames I guess
And then compound that by your counterintuitive assertion being generally wrong in most useful cases. He is either interviewing very junior candidates or frustrating a lot of people.
i.e. You could get sharp candidates that know the correct technical answer but intentionally give the wrong one because they rightly concluded statistically odds are the interviewer is on conventional wisdom wavelength.
Could be good if you're specifically looking for someone good at mindgames I guess