Why work to make the interviewer happy again? If your solution is better than the interviewer's you should expect the interviewer to acknowledge that fact, like an adult and like a team player. He is not supposed to be offended or unhappy.
Wanting the job might be down to you needing money. OK, use the soft skills, and make the interviewer happy. If you don't particularly need the money right now, then evaluate whether you want to work with this interviewer at all.
But yeah, if you get to interview with the boss and they are a problem for you, then that does matter.
Also you are in a better situation if you get the job offer - they want you -, and let it go because you learned about them - and you don't want them anymore. Get the offer.
And end of the day, interviews are also a chance for candidates to evaluate the company