If I were to take a broad swing at the reason I'd say the music covers the noise of the elevator. As they got quieter the music was made redundant.
In some ways, it feels like as visual aesthetics went minimalist, so did the soundscape.
I'd personally like to hear an even quieter soundscape. It's so annoying to be sitting in a bar or hotel with sound blasting at you. It's like they expect people fear being alone with their thoughts or to be unable to make conversation when together, so they feel the need to fill the void.