When did poetry separate from music? What is the reason for the separation?

It is not accurate to say when it was separated, but the reason is certain, that is, in the process of circulation, the music score is not as tenacious as poetry and gradually loses its vitality. Because in ancient China, the popularity of music was far less than that of writing. Poetry, as lyrics, can also exist as a kind of reading or reading text after being separated from music and spread by copying everywhere. Everything that can be read can be handed down, whether orally or in various works and classics. Simple music is mainly passed down by artists, and few people can understand a single score, so it is difficult to spread. In fact, people who can read or even write music scores are mostly literati who love music, such as Jiang Kui and Li Yu. As the main force of singing and playing music, folk artists have few opportunities for education. In addition, it is also common to quote poems in various ancient books, but few books will quote music scores, which objectively reduces a channel for preservation.