I would think people of almost any age would find it interesting - the reactions would just be different. Small children often like dinosaur bones, or leopards, or dogs.
Sooner or later, movie watchers or book readers will be introduced to the (unfortunate?) trope of someone in an incorrect engagement who finds a better person in the end. Possibly BuB is the best movie to begin that with, although it isn't clear to me that David and Susan will be happy for long.