People who were spoiled as children (or are spoiled children) are usually depicted as unpleasant monsters who insist on getting their way always, and for sure they exist but I’ve also met a lot of spoiled people, children or adults, who were super nice and generous because they were brought up with the knowledge that if they let someone else have something or give away one of their possessions they’d just get another one and that carries over into adulthood where they might not get another one but they still don’t feel the same attachment to material things.
So in my experience whether spoiled people are unpleasant have more to do with the values instilled in them by their parents as well as their general personality. I know one boy who won’t give anyone anything despite his parents giving him everything he wants and another who will hand you his entire birthday cake if you ask because he trusts that you’ll share it with him and if not his mom will get him another.
So nice spoiled people in fiction like Carlotte from Princess and The Frog aren’t unrealistic but they are probably a lot less satisfying for a lot of people.