I probably didn’t explain it well. It may be partly status and charm, but there is an attraction to a school like St Andrews with old buildings you wouldn’t find in the US, as opposed to “red brick”. The fact that Prince William went there adds romance, but also makes Americans think it is a place where British aristocracy not smart enough to go to Oxbridge go. In the US, there is prestige for some people in going to a college that is “preppy”, and Americans might have the impression that is true of St Andrews.