I don't think you understand the way the music industry works. When you say publishers, I think you mean music providers. Apple is not a music publisher, they are a provider of music that is owned by a publisher, created by an artist that has songwriting rights. When a song get "performed" a royalty is paid the the songwriter and the publisher. Artists have complete freedom to retain their publishing rights to transfer them to someone else. That is not the issue here.
Surely you see that power is very unequally distributed in the music industry. Beyonce would be able to negotiate very favorable deals because a radio station, or streaming service would want her badly, while a new artist would have no power. That's why we had payola back in the day as radio stations took kickbacks to play certain artists instead of others. Today the tables have turned since music is more of a pull than a push.
This is the same kind of concept as a minimum wage. The government should be providing protection for artists by setting a standard rate that they are all compensated for when their music is performed. Apple is trying to simplify the process so that the whole thing is more standard and more fair to the owners of the music.