Funnily enough, I was using ChatGPT for the same purpose a week or so ago. You can ask something like:

> I'd like recommendations for book series that avoid self-pity, misanthropy, nihilism, and over-indulgence in self-identity analysis. Lessons on character building and virtue can be present but ideally without overt moralizing. Characters should simply inspire through their actions. Starting from Curious George, and working toward things like LotR. Background themes should lay the groundwork for stoic and transcendental philosophy later.

If you then ask for series to avoid, at least in my session Wimpy Kid is explicitly named. Or more succinctly it basically told me I want pre-1970s children's literature and adventure fiction and stay away from contemporary school-market YA.