The issue is why would people suddenly be willing to pay for a 4-piece band, when they used to be able to get a 30-piece band? There’s no denying that music would have evolved anyway, but it would not necessarily have evolved in the direction it went.
My own view is that we have reached the end of music. I don’t mean nobody will ever play music anymore, but that the era of music being improved is over. Everything has been tried, and as I look at the music scene, all the music currently being “created” is mostly awful. Rap, with the recitation of foul lyrics to a beat with minimal melody, represents the absolute nadir of music creativity. I laughed years ago when people said only so much good music can be created. Those people were correct, and I’m not laughing now. The current music scene, in whatever genre you choose, stinks. Said the old fogey Driftless.