Because sudoku is a math puzzle and a book of words is a story.

Like, the line between big artistic/creative efforts and other stuff is subjective and hard to trace, yes. I know the counter arguments here (“what if the book is an instruction manual?”, “what if someone’s labor of artisanal love is making sudoku puzzles?”), but sudoku vs story is like disagreements over “what counts as the Midwest”: you know very well that Antarctica isn’t in it, and that a sudoku book merits very different appreciation and artistic protectionism-from-AI than a story.

It’s fine to categorize things without having a rigorous definition of the category.

She is not generating Sudoku puzzles, so you can drop the hypothetical. As for the implication that good sales figures mean people enjoy the books she generates, might it be possible that the reason her books sell are because she stuffs storefronts with so much slop (see the figure in the title) that she outcompetes everything else by volume alone? Regardless of quality, whether people like her books, and with no regard for authors who use higher brain functions at the cost of spending more than a day and a half writing a book?

It's unfortunate this needs to be explained.