I've just bought S21 Ultra and its Smart Clear View and I've noticed this limitation: if I activate brief popups with edge lighting when screen is off, because I want to see notifications just when they arrive, instead of using AOD, these don't work at all with Smart Clear View cover. Ok, this makes sense because the cover hides the edges, but there is no effect in the Clear View window. I would expect to see the popup there, or the AOD to appear for a while just to have a visible notification, instead just the sound and vibration happens.
What about letting the AOD to appear for 3-5 seconds on new notification? This may be helpful also without Clear View cover (since the notification LED is gone), but it's fundamental with Clear View cover. At the moment the only way to have visible notification is to let the AOD always on when using Smart Clear View cover.