Have you ever read a story—whether a novel or a children’s book—where you rolled your eyes at the unbelievable? In fantasy and fairy tales, we expect to encounter extraordinary or even absurd characters, people, and settings. That expectation allows you to continue on and enjoy the story despite the fiction. But if we experience a contrived plot or unfactual statement, no matter the genre, we feel cheated and deflated.
I would say the genre of Heretics of Piedmont, historical fiction, has a similar but deeper challenge.