But there are no (effective) guardians of the monoculture. Sure, advertising and marketing strive to offend the fewest number and thus sell more, and that limits the imagery they'll use; but there's no group of five old white guys meeting in a room under the North Pole and deciding that necklines will be up this year. There's no they there.

(From your description of the 20s vampire story, it sounds as though those emotional/superstitious immigrants are right. No?)