Without studying the poet, we can't know the purpose of his writing and the background of his writing at that time, and we can't accurately grasp the content of poetry.
There is an article written by writer Bai Juyi called "Articles are written in time, and songs and poems are written for things." "Also in explaining your problem. Since the author wrote an article and a poem, it must be something happened, or the author experienced the feeling of something, or touched the scene and so on.
Since it happened, we should express our feelings, but what are we expressing our feelings for? That must be writing poems and articles! Therefore, a poem can contain many things. How can you understand these things without knowing the author? You know, if you want to really understand a poem or an article, you can't just rely on your own speculation. People who don't know the author can't read ancient poems.