The reason for this is that content creation is no longer about the content per se, and I say this as a content creator myself. Content created today serves two functions beyond actually producing something that another person will appreciate for its artistic beauty:

(1) It serves as a place where other people gather to interact. People gather in such ways now more than ever because of the loneliness created by advanced technology. Therefore, being trendy is more important than being artistic. That's why total garbage like the Avengers movies is so successful: it's because it panders to the lowest common denominator and therefore is an ideal gathering place for the lost souls stranded by technology.

(2) If content is not a place for people to gather, then it is simply content that teaches other people to produce more content. In fact, some of the most successful content on YouTube is simply content designed to help people produce other content that no one will watch most of the time.

While both these functions were active to some extent in humanity's past, it is only now that they function to their full extent. They are magnified by modern technology and other reasons for art are being minimized.