I agree with this, but also note that a lot of children's books written by humans (I suppose) are terribly bland. My daughter has some Disney books which has illustrations from the films, and the writing in those is exceptionally bland. Same goes with some wonderfully illustrated, but terribly written, books from the 50s and 60s. I'd actually much prefer reading her GPT stories than those books which we have on the shelf (I guess I should get rid of them actually).
There are also a lot of really nice books for children, with great plots and illustrations. And you can actually read them before buying, if you go to a bookstore.