That’s really what I was thinking - that the graph probably wouldn’t change much if you remapped it to personal connections because the pattern of personal connections is probably what drives it in the first place. Hence my favorite musical era is when my connections peaked around age 30. Although tbh most of what I liked then and still do is what you would call “popular gunk” - never did care much for dismissing popularity as low quality. They often go together, but unpopularity and low quality also do.