The biggest one I can think of is The Catcher in the Rye. It is a good book, and if someone likes The Catcher in the Rye it means they are well-read. If someone says it is their favorite book then they probably identify with it too much and missed the point.
What are some other examples of this that you know of?
That’s a narrow point of view, to judge someone by the books they like.
Books are supposed to help broaden your perspective and process complex emotions. Sometimes a book will resonate in unexpected ways. This is not a tell to a person’s morality.
This mentality is what leads to book shaming and book bans.