I am not sure if the lyrics of jazz are better than those of other singers. I mostly liked Fatz Domino his trumpet because my grandfather played one but at times jazz also gave me an headache. Watched The Aristocats?
Soon no one knows history, componist, artists, directors of films, books (literature) art and worse...most will not be able to read.
I admit that I don't listen much music, I live in the past in music styles. When I was saying news music don't have good lyrics I was thinking in singers like Daddy Yankee, others reggaeton singers.
I agree with you about the losing of knowledge, here even the teachers have problems reading and understanding.