Originally Posted by
Spectre17
I can't speak for others, but I find them annoying because they don't fully dim.
I thought that myself when I first encountered them. I dimmed my window as far as it would go, and was surprised that I could still see out it to some extent. I thought "gee, the cabin is not really going to get dark even when all are dimmed all the way" but when that was the case, I thought the cabin was plenty dark. From what I remember, it's not any brighter with all of them dimmed than is the case with the few ambient lights that are always on.
The other thing is that they can be under flight attendant control. That's frequently a good thing (dimming windows that sleeping passengers forgot to so that sunrise doesn't blast the whole cabin), but sometimes the FAs just lock them in the dimmed state, which is annoying if you actually want to look outside.
That's a feature, not a bug.