I think Nasser's back was an area on his physique where he needed very specific conditioning and posing to make it look good. I think even the backstage pump made a huge difference for him. If even an element of the above were out of place, Nasser's back would look drastically different [for the worse] yet it could be up with the best of them if the above conditions were in place. Compare that to Nasser's chest and legs which looked good even when he was well over 300 pounds and off-season. I think some bodybuilders in some particular areas need a very specific protocol to make things look good.
For example, look at how increased body fat affects the chests of both Jason Huh and Ben Pakulski. While Jason Huh's chest looks thicker than ever, Ben's disappears as it blends into the rest of his torso. I wonder if perhaps my lack of chest is affected as strongly by body fat. I guess I can't know unless I cut down but the photos below are rather fascinating with respect to just how conditioning affects some bodybuilders and not others, in terms of specific muscle groups: