However, The Planets was the second thing on the bill. The first thing was the world premiere of a modern symphony, and that was a long, hard slog. Ravel is supposed to have described his Bolero as twenty (?) minutes of orchestra without music, but he was a bit premature. One of the hallmarks of virtually every genre of music is the repetition and elaboration of themes and patterns. Bolero may be more repetitive than usual, but it has an identifiable theme which is elaborated on as the piece progresses.
Modern "classical" music has pretty much thrown that out. It's more musical than beating on the keyboard of a piano like a wild monkey, in that it consists of recognizable musical phrases, but they aren't connected to each other or any larger pattern. It just wanders around. It might be OK as the soundtrack to a movie or even a dramatic reading, where the music is meant to relate to something else rather than itself, but in the pure form it's very tough to appreciate.