"So the big push from Sony, not just at Naughty Dog but at all of Sony's development companies at the time, was to craft games for PlayStation 3 that were much more realistic. The pressure from Xbox's success with gritty shooters was a very real force on our direction at that time."
Apparently the suggestion wasn't met with universal enthusiasm from the studio's staff.
"We had a lot of internal grumbling about the realist bent. More of the old dogs were from the Crash and Jak era and preferred that more whimsical style. But alas, that was a losing battle."
I guess Uncharted was supposed to be Savage Starlight, huh?