That guy was going to be my new manager, had I accepted the job. I had no interest in working for someone who could not handle being wrong.
I had a similar experience early in my career (early 2000's). I interviewed for a data analyst job dealing with survey data, and the hiring manger (the only other database programmer) asked me a TSQL question where he had a specific answer in mind. His answer was to use a "@value is >= x and @value is
He told me that my answer was wrong, so figuring that I'd already lost the job I argued my point. He believed I was wrong so strongly that we relocated the interview to his desk so that he could prove me wrong. The interview ended when he found out that I wasn't.
Dodged a bullet on that one.