While the article focuses on the UK, Taylor Swift's dramatic and public exit from Spotify suggests that US artists are thinking the same things. Ultimately, the issue revolves around how to maximize profit on an artistic production. Artists and labels both feel that streaming revenues are too low to justify full and immediate release of new content to all streaming sites. Consumers on the other hand don't want to pay.
The bigger question for providers of content is whether or not the streaming model is sustainable or will fade out?