Getting Feedback After a Job Rejection

Five years ago, I applied to a visitor services position at a museum that I was really hoping to get, and had a positive interview experience. Sadly, I didn’t get the job, but someone gave me that tip that I should ask the interviewer about the outstanding qualities they found in the candidate they ended up choosing as a way for me to get feedback for improvement. Have you ever received feedback from a potential employer about your interview performance or how they perceived your skills and experience? Is this too much to ask?