There were some very high level personnel differences in the production of Uncharted 2 and Uncharted 3.
Justin Richmond was hired FOR Uncharted 2's multiplayer mode, and somehow became game director on Uncharted 3, which I have to admit I wasn't a fan of.
And to me Uncharted 2's writing, pacing and even game design was just miles and miles better than Uncharted 3. Uncharted 3 was fine, but it was not the same transcendent experience Uncharted 2 was. By transcendant, I mean Uncharted 2 really and genuinely distinguished itself from the pack. It avoided a lot of the tropes of story in games, it was subtle and respected the audience. It had a fantastic focused cast with next to no fodder.
Somehow Uncharted 3 managed to forget all of these things, it was gamey, offered too much exposition and had a slurry of cast members ducking and diving, in and out for no apparent reason.
It's unfair to put it down to one person, but I do think Richmond's impact was felt in the gameplay, where all of the encounters felt ridiculously busy and at odds with the story just to inject some frenetic action. There were so few minimalist or subtle enemy encounters, in comparison to Uncharted 2. It always involved dodging myriad lasers, throwing back grenades, while beating up armoured dudes and trying to fend off the fodder. I also, almost feel it was too arena-like, which I usually like. But I feel all of Uncharted 2's encounters were more interesting, because they were funneled. They did actually feel like multiplayer.
But basically, given how Uncharted 2, Uncharted 3 and TLoU turned out, I have utter faith in whatever Naughty Dog does with Uncharted 4 anyway. I just hope they try to be a little bit adventurous, rather than putting out another linear action adventure.