Never say 'No offense, but' to answer the HR manager's last question

I've been interviewing people for over 20 years for various roles from maintenance electrician to IT manager. The one that stands out the most by a large margin was an IT analyst candidate about 4 years ago at my current company. He was qualified, had relevant experience, so I'm sure we would have done a second round, but just before wrapping up the verbal part and taking him on a short plant tour (we're an automotive supplier) the female (foreshadowing) HR manager asked her normal last question "Why are you looking to leave your current company?" It was just me and her doing the first round, she was across the table from him. He put his hand out toward her (big table, not anywhere close to personal space or anything) and said "No offense, but it's a female owned company" then went into a long diatribe about how she's crazy, doesn't trust anyone, etc. No words. She looked at me after he was done talking, didn't have to say anything. I took him on a 'plant tour' which was out the door to the plant floor then along the wall to the main employee exit. Still to this day, I can't understand how someone can be so unaware.