>I'd take out the filler "journey" bit, add in some conflict between the mom and kid, and make the ending more realistic (fairy uses magic to make icing for the cake?). That might bring it up to library-filler tier book.

THIS. This is exactly the power of these models. The AI generated an entire story in some extremely quick amount of time and an experience Human can edit and curate the results. It generates first drafts trivially.