As Kelefa Sanneh wrote, "A rockist isn't just someone who loves rock 'n' roll, who goes on and on about Bruce Springsteen, who champions ragged-voiced singer-songwriters no one has ever heard of. A rockist is someone who reduces rock 'n' roll to a caricature, then uses that caricature as a weapon. [...] Countless critics assail pop stars for not being rock 'n' roll enough, without stopping to wonder why that should be everybody's goal. "
Rockism is an adjective that most people don't want applied to them. Jody Rosen says "that most rock critics would rather be accused of pedophilia as rockism." The implication is that they are close minded.
The other word is, Poptimism or Poptism, which is the esthetic of Pop culture, or in this case Pop music. There is a pun there with the word optimism, and the idea that Pop culture is an optimistic open culture that incorporates everything it finds without (much) critique. The more capitalist definition of Popism or Poptism is whatever sells is good. It is whatever wins the People's Choice Award.
The opposition of Rockism and Poptism occurs because Rockism looks backward to an ideal past and Poptism does not care about the past -- it embraces the trendy present without much concern for the future. One might pair these like conservatism and liberalism, but it is also like conservatism and nihilism.
I want to tie Poptism to the philosophy of Natural Language, or the notion that language is what people speak, not what dictionaries and grammers say they speak. Natural Language got knocked when during the Ebonics movement, when people tried to teach Urban English in schools. It reminds me of American English in the sense that new words are accepted from whereever they come. Unlike French or Dutch where authorities decide what words are worthy enough to enter the language.
Poptism isn't really anything, but it is the name for whatever people do collectively.
