SoundScan, raising the drinking age to 21 and MTV changed pop music forever. Prior to SoundScan an artist had two, maybe three albums, to find an audience. No more. And raising the drinking age killed a lot of the music venues that depended on liquor sales to stay open. MTV, of course, put the nail in the coffin.
What most people don’t realize is that there is no “Hollywood.” There are five/six major corporations — Sony, Disney, Viacom, Time/Warner and News Corp, Bertelsman — that create 95% of pop culture.
All true, but there was another shakeup in the early 90s when Billboard added WalMart and the other department stores to their polling data. And the TV rating system is way overdue for a shakeup.