The expression “Zukunftsmusik” was spawned by media mockery.
A figure of speech comprised of the two nouns “Zukunft” (future) and “Musik” (music), it was invented in the 19th century by a Cologne-based publisher to poke fun at composer Richard Wagner’s works as, well, “future music.”
But today this expression is no longer merely a form of mockery. It is simply used to describe a project, or an event, or anything, really, that just might – but won’t necessarily – happen in the distant future.
Germans might hence say about, for instance, zero-calorie butter, a debt-free eurozone, or pigs that fly: “Aber das ist doch alles noch Zukunftsmusik!” (But that is all just music of the future!)
So “Zukunftsmusik” is used in a tongue-in-cheek fashion, to be sure, although it can also be used in a more serious manner, such as to describe the hopes and dreams of people. For instance if a little girl dreams of becoming a prima ballerina when she grows up or a little boy dreams of becoming a fireman, their parents might then very well say that this is all still just “Zukunftsmusik.”
Similarly, if someone envisions their future as getting married, running for political office, or publishing a novel, they might call that “Zukunftsmusik” with an air of optimism and hope for achieving some goal or personal milestone which may or may not be on the cards for them in the future.