Man I don't know. There are times where the atmosphere is pouring out for me.
Other night I was wondering around Boston, hearing gun fights in the background a few blocks away. The entire area was foggy and creepy, going from block to block checking things, getting ambushed by Mutants and Raiders. Then as I finally made my way out of Boston into a Marshland the sun was setting and mist started rolling in and it was raining. It was eerie to me and I was playing at night with the lights off and the sound up. It was pretty amazing to me and put a huge smile on my face.
Yeah, one of my recent favorite, "Ah ha!" moments was when I stumbled into my first super mutant outpost just as my first radiation storm swept in. The firefight was disorienting and chaotic as I had no experience with either of the two mentioned elements. Then a third new experience occurred simultaneously as some skinless synths joined the fun.
The whole scene was just nuts and had me on the edge of my seat until the last baddie dropped. It brought into relief how immersive atmospheric the game can be. This is with the full understanding that the game can be downright ugly at times.
But man, when it shines. It SHINES.