The sky is a lighter blue, but I don't see "much" brighter. You can still see the airplanes fine, the hangers fine, details fine, just a more elaborate sky. I see more contrast, not necessarily a darker environment. It's hard to tell if that 2008 version was taken in the daytime or not.
Remember, the game sun doesn't actually give us the light, sky color doesn't necessarily determine brightness. The sky could be black but you could see things, it's about the contrast between objects.
I see better realism.