In my experience, the opposite is true: people who feel insecure about the cultural products they consume tend to take refuge in a vague relativism that allows them to wage a blanket defense of those products without actually having to, you know, defend them. It always comes across as a bit of a cop out to me: "Yeah, well, it's all equally valid!"
But that doesn't pass the fundamental smell test, because it's hard to credit that anyone would seriously believe the obvious implications of such a statement (that, say, the New Kids on the Block reunion tour is as artistically valid and significant as a Beethoven sonata). It's sort of the intellectual equivalent of ignoring the dead skunk in the road: you can close your eyes real tight and hold your nose for dear life, but are you really convinced it's not there?
Probably not.
Personally, I'd say there's always room for disagreement, discussion and debate, but that such discourse ought to be handled in an intellectually honest fashion. You don't have to like what other people like. You don't have to derive enjoyment from the 'classics' because everyone assumes you should. You can enjoy stuff that, in your heart of hearts, you know is piffle. It doesn't make you a bad person. Or stupid. Or inferior to someone with more exacting tastes. But if you're going to defend the artistic validity of a particular choice of yours, at least do so in a manner that allows for conversational give and take, instead of trying to head off any discussion with broad platitudes which admit no room for discussion.