Is this the "black crushing" I'm hearing about. Seems to only affect my lock screen (which should be all black). Defective?
Don't know but it's bugging me, too. It's making my Swift Black notifications look klutzy.
At first I thought it was bleed through from the home screen wallpaper, but I can still see traces of that crummy radial gradient lighting effect even using the blackest wallpaper in the Pixel 2 set, "gooey licorice." Now I'm wondering if it isn't connected to the transparency effect tied to the app drawer in the Pixel launcher.
Different ambient lighting qualities can sort of mask it, oddly enough. The lockscreen usually looks a bit better (i.e., more like solid black) when the room lighting is very bright. I couldn't really see an obvious difference between the notifications and the lockscreen wallpaper at work, but I see it all too clearly at home, where I typically have only one or two lights on at a time.
Also doesn't make a difference if Adaptive Brightness or Always-On Display are ON or OFF. Turn brightness down to around 20% with AB on, and you can mask it, but your display will look like its dying.