The song playback screen of the music app comes across as a confused design. OS X and iOS have taught us that vibrancy reveals something underneath. This itself is not entirely unproblematic (https://forums.macrumors.com/thread...t-quite-work-in-safari.1939017/#post-22270280).
Yet in the music app the vibrancy effect is used simply for decoration:
You could argue that the entire music interface is intended to be represented above an image of the album cover of the currently-playing song, and this is what bleeds through the interface. Indeed, it remains in the interface in the Up Next view. But this isn't well-communicated, and seems superfluous.
No doubt the design would look a little stark in the absence of these bleeding colours but it completely contravenes what the OS has taught the user so far.
Yet in the music app the vibrancy effect is used simply for decoration:

You could argue that the entire music interface is intended to be represented above an image of the album cover of the currently-playing song, and this is what bleeds through the interface. Indeed, it remains in the interface in the Up Next view. But this isn't well-communicated, and seems superfluous.
No doubt the design would look a little stark in the absence of these bleeding colours but it completely contravenes what the OS has taught the user so far.