Here is an interesting consideration:
Static noise has the most rich, complex texture but no pitch.
A sine tone has the most defined pitch but the smoothest, least complicated, most minimal texture.
Listening to either for a prolonged period isn't as nice as listening to music. Both of them become monotonous in their own way. Although you can definitely meditate to a sine tone. But what about static noise? It's so random and complicated that the temptation is just to switch off your brain and it all becomes one homogeneous texture.