Labels have been cooking the books and running dirty schemes since forever. Hell even Pink Floyd wrote a song about it.
I would not be shocked in the slightest if a few artists are increasingly also starting to throw their weight around and that is gaining some traction and becoming more of a norm as well. Thats also not new, ranging from the inane (no brown m&m's back stage) to stuff like this.
I think a lot of people would be shocked to learn that
1. Many artists dont write their own songs
2. Many bands dont perform in their own studio albums and often use hired guns/session musicians
3. A lot of 1&2 are actually a relatively small number of people with a pretty prodigious output.
People like Max Martin, Ryan Tedder, Sia Furler, Dr. Luke, Bonnie McKee in the current sphere/conversation.
But even going back to Elvis...Jerry Leiber and Mike Stoller are the actual writers for Hound Dog, Jailhouse Rock etc. And theres some for other Genre's, Motown had their own with Lamont Dozier and Brian and Eddie Holland. Otis Blackwell, Prince Nelson Rogers etc etc.
This revelation happened for me when i started getting into playing music. Over the years I have gained appreciation for those that dont really need to deal with 1 and 2, but that takes a very special type of talent and dedication.