Yes, I may well be wrong about the anticontext shrinking, though I think maybe the reason it isn't shrinking for people like you and Kevin and Dave and me is that we come from a tradition which is pretty alert and alive to anticontexts - whereas, as you say, the teenpop primary audience aren't so much.

(And actually is the becoming-aware-of-ones-anticontext a defining moment in childhood - the awareness that there are a bunch of people who think what I like is lame (or who like lame stuff I hate) and the reaction to that.)