More than likely it won't come to this. Most musicians want their music everywhere, and give it away for (almost) free. Spotify/radio/etc are the marketing, and

More than likely it won't come to this. Most musicians want their music everywhere, and give it away for (almost) free. Spotify/radio/etc are the marketing, and concerts/festivals/movie licensing/etc are the product. Unlike movies, there's insane repeatability of music, meaning it can be everywhere. I wouldn't be surprised, though, if less-popular tracks for artists moved to another service. You want to hear The Chainsmoker's radio singles? Play them non-stop on Spotify! But if you're a huge fan and want to hear back tracks, demos, etc, you can pay them $10/mo on a Patreon-like site. Basically, charging more for a closer relationship to studios you like, while their more popular music is released for free.