When I was in high school and college, I listened to music produced by individuals about 10-15 years older than me. So did the Boomers. So does my 13-year-old niece. I would guess that the inordinate cultural influence of these writers and musicians is due to the number of boomers, not the innate "betterness" of their work compared to everything that has come since then. Madonna influenced an entire generation, too, but that doesn't make her the best singer of the age. Perhaps the Boomers are still driving cultural trends.
The Boomers came of age in a common culture that has all but disappeared. I'm not sure at what point things become irrevocably split—Cable TV?— but shared cultural experiences today are far more rare than they were 40 years ago. We may never see such a sizable "voting bloc" again. (via jch)
