I would define merit as either virtuosity or innovation. You know, progressing or redefining their art form, pushing boundaries. Also critics don’t examine the technical details of something. For example you wouldn’t read a review that said “This song was in the key of A Minor, follows a 2-5-1 chord progression, has a tempo of 120 bpm” because that isn’t a critique, that is a description. A good critic would criticize their performance. A good critic would also spend their lives studying whatever they are a critic of, trying to remove all biases they have. I would say doing so would give you more weight in what you say makes something good or not. Would you go to a electrician for an opinion on plumbing? No, because they haven’t studied extensively on the subject. I think that attempting to distinguish quality art is a better option than throwing your hands up saying everyone’s opinion is equally valid. Also I never claimed I was a perfect critic or even that critics I like are perfect critics (or any critic for that matter). There is plenty of music that I dislike, but I feel as if it has musical merit. For instance, I don’t like rap music but I respect Eminem for his wordplay and speed at which he can rap. He is clearly a virtuoso who makes good music, although I don’t particularly like it myself because of my biases. On the flip side of that I like some disco music, which I enjoy but I don’t feel like that is good music. It is very simplistic and repetitive and a lot of songs sound alike. A guilty pleasure if you will. I think anyone can enjoy any art they want too, but I think those who actively study and critique art would get greater fulfillment from that art by doing so. I just think that certain art has more effort, intention, or talent put into it and it should be recognized as such. (Sorry for wall of text, I suck at formatting on mobile)