There are no "incorrect" opinions. They're opinions. They can be spawned from a different ideology or a different set of moral or intellectual priorities, they can be tainted by incomplete or outdated information or malformed assumptions. But they themselves can't be "incorrect" per se: they're subjective.
There are also no incorrect points of view. They're points of view. They depend on the perception of their owner, who has a different way of seeing things, different experiences, and different impressions depending on the individual.
For them to be incorrect, there need to be "correct" opinions or points of view; and to claim there are correct and incorrect opinions and points of view is invalidating freedom of speech and freedom of thought.
If anything, people may make a mistake and express it through their opinion, or let it taint their point of view. But in things so subjective like the quality of mainstream vs non-mainstream music, especially considering the multiple factors that are involved in the experience of enjoying a piece of music, there's no wrong or right. No one is wrong for enjoying that dumb "all about the bass" song (for example), and no one is "in the right" for saying music is worse now because people hear that instead of, say, Mussorgski's Cum Mortuis In Lingua Morta.
And it's much healthier for us, chipmusic enthusiasts, to think this way; especially because in terms of musical elitism, it can be applied back to us. "In my time people played real instruments, they didn't try to play music with toys*."
* An opinion that would be formed through incomplete information: see Leopold Mozart's Toy Symphony.
