Because the authors were AI-fearful luddites. From "Book" to "Program that judges books" lies well beyond any argument that the use of the derivative work could

Because the authors were AI-fearful luddites. From "Book" to "Program that judges books" lies well beyond any argument that the use of the derivative work could supersede the original. It's such clear cut transformative use that the authors come across as grossly misinformed about copyright law as a whole. Perhaps there is an argument for generative AI possibly superseding the original, in that people might start asking an AI to generate them stories "in the style of x" instead of buying the author's books, but this wasn't that. It was just some fun data analysis of books.