Even ignoring the AI, if you look at the movies and books that come out these days, their quality is significantly lower than 30-40 years ago (on an average). Maybe people's attention spans and taste is to blame, or maybe people just don't have the money/time/patience to consume quality work... I do not know.
One thing I know for sure - there is enough high quality material written before AI, before article spinners, before MFA sites etc. We would need multiple lifetimes to even scratch the surface of that body of work. We can ignore mostly everything that is published these days and we won't be missing much