I’ve been on both sides of this and when you’ve spent the whole day talking to a dozen people who all seem competent enough to do the job, you go with the person that either has a little more (or more relevant) experience, or whoever you enjoyed talking to the most.
I’m a huge dork, so if you happened to mention something like D&D or Fallout during the interview, you’re probably going to get it. (Assuming everyone is equally qualified.)
But at the same time, I’d never mention anything like that at an interview, because I wouldn’t expect the interviewer to appreciate it.