I'm sure if we had been around one or two hundred years ago there would have been a lot of trash that would have had us despairing of the music being made. What survives probably has survived because it was the best. There will be music surviving from these times as well. Think of some of the wonderful "folk songs" that have been written in the past ten or twenty or fifty years, and more from our generations may endure because of its wide circulation.
Woody Guthrie, Jimmy Driftwood, Stan Rogers, Pete Seeger, Eric Bogle, and so many more.