So I don't know anything about this app really or its evaluations but I think applying it to acclaimed fiction is not a criticism of applying it to a newspaper

So I don't know anything about this app really or its evaluations but I think applying it to acclaimed fiction is not a criticism of applying it to a newspaper article per se. News articles are meant to convey concrete information relatively concisely. So metrics like sentence length and complexity and adverb count are at least in theory valid things for it to measure and aim to reduce. Now whether it effectively measures those things I have no idea or opinion about. I didn't know it existed until ten minutes ago but if I had I definitely would have predicted that most highly respected fiction would break its rules all over the place.