I've been rather fond, for example, of this thought experiment by writer Michael Chabon, but I'm far from certain about pursuing it:
Imagine that, sometime about 1950, it had been decided, collectively, informally, a little at a time, but with finality, to proscribe every kind of novel from the canon of the future but the nurse romance. Not merely from the critical canon, but from the store racks and library shelves as well. Nobody could be paid, published, lionized, or cherished among the gods of literature for writing any kind of fiction other than nurse romances. (from the introduction to McSweeney's Mammoth Treasury of Thrilling Tales)And naturally, as a composer of notes rather than words (those damned defeating words) , the mind wanders to consider what, roughly or exactly, would be the equivalent of nurse romances for a composer of contemporary art music, circa 1950. Electric organ sound tracks for the waning radio soap operas, perhaps. Or music for health education films. Or music to accompany upscale shopping or tearoom dining. Or Sweet Adeline quartets and choruses. Or Salvation Army Band revival songs. Or Girl Scout campfire songs. There's no exact parallel, no precise fit, and it's hard to imagine any of these genres being able to accomodate everything one might want to do — technically, expressively — as an art music composer. But a little tourism among non-arty genres does quickly suggest that there is scarcely a genre or musical topic area from which an art music could not, at least, potentially avail itself, while the opposite potential cannot be said to exist for such genres, which are tightly constrained.
Let me be clear that the art music treatment of genre material is not the same as the synthesis of new repertoire for the given genre, for art music takes the generic and places it within a unique frame, contextualizing, interpreting, and commenting on not only the material but the genre, circumstances and milleau from which it comes, an operation involving a simultaneous distancing and appropriation, a combination which is, usually (but not quite always), scarcely possible within a well-defined genre. I realize that there is something of an imperialist tone to this enterprise, and we should, of course, proceed with great ethical and aesthetic caution. Otherwise, we risk falling into the trap of (that famously imperialism-serving) composer Karlheinz Stockhausen, who once (famously) insisted to Morton Feldman that Feldman's music could be a Moment in his, Stockhausen's, music, but not the other way 'round, totally misunderstanding that the placement of Feldman's music into a series of Stockhausen-y Momente would completely rob the music of the formal and material framework with which Feldman's music is identified.