Hello @Mike Foran,
I do see the change in behavior you mentioned. To be clear, this is the label box in the timeline Label column, and also the color used when assigning a lable color to keyframes.
The timeline bar to the right, which is informed by the label color, changed slightly based on the UI slider in previous versions of AE, so I would expect that to still follow variation based on theme.
Are those the same expectations you have for label behavior?