Also I'm not precisely sure what "objective territory" SM was getting into.
If the idea is that experienced, informed opinions on the aesthetics of music should be valued more than layman, or inexperienced opinions - well, first off, I don't necessarily agree with this, but even then I don't think this represents any sort of "objectivity" at all, because people consistently demonstrate an ability to ignore the credentials of expertise, formal education and experience when it suits their tastes.
The idea of "valuing expert opinion" isn't really offensive to me because it smacks of snobbery - it strikes me as wrong because- in practice, it ends up being an after-the-fact way to justify your own personal tastes under the guise of objectivism. It's a sin of disingenuity, not necessarily snobbery.