This question involves many factors, including the motivation of the novel creation, the change of the reader group, the change of writing skills and writing style, and so on. Although it is impossible to accurately evaluate all novels, the writing style and storyline of some novels may become more and more old and lack creativity due to the change of readers. Some ignored the tastes and needs of modern readers. They might pay too much attention to writing and rhetoric and ignore the appeal of the story and the logic of the plot. Changes in writing techniques and styles could also cause some novels to become more childish. Some of them ignored the meaning of the story and the depth of the plot. They might be too reliant on the writing style of Xiao Bai and ignore the true literary value and depth. In summary, there were many reasons why the novel became worse and more childish. Constantly improve your writing skills and creativity while maintaining a deep understanding of literary value.