Take this with the traditional grain of salt, but reports have been coming out in the wake of the game's closed doors demonstration at E3 2016 that The Last Guardian is a little rough around the edges. Ten years is a long time to make a game, and games don't take that long just because "they want to get it right for the fans." It means something is wrong.
VG24/7 reports that the phrase “It’s like a PS3 remake” was spoken a lot by journalists who were able to get into one of the four-person, hour-long hands-on sessions with the game. Textures are reportedly "flat" and the game's lighting and particle effects are described as "positively prehistoric."
IMO, the trailers seem fine for the most part, but it is possible that the build present fro the hands-on demo was an old one. But then, if it were old why would they want to show it off?
That said, it's not just the visuals that seem to be suffering, but the controls and camera have been seen as problematic. One of the bigger issues reported involved the Jump and Grab inputs, which were configured to the Triangle and R1 buttons respectively. The in-game prompt only instructed the player to tap triangle button, but if it was not followed by R1, the boy would simply fall to the ground.
To be fair, this is a pretty similar set-up to the controls from Shadow of the Colossus, which would involve a similar Jump and Grab scheme while you scaled each Colossi. In this instance, it's hard to tell whether these journalists simply haven't played a Fumito Ueda game or if the set-up is legitimately frustrating in the context that The Last Guardian provides.
As far as controlling the boy, The New Zealand Herald reports that inputs for controlling the character are "laggy and imprecise, and the camera as it stands is fairly atrocious." While according to The Guardian, "Sometimes your viewpoint gets weirdly stuck at a certain angle, sometimes the way ahead can be annoyingly obscured, especially when Trico wanders into the space between the camera and the boy, occluding everything."
I have a healthy skepticism of games that attain "legendary status" on the basis of what they could be, rather than what they are, so I am inclined to believe that The Last Guardian is going to have some issues. That said, I think that anyone who has played and enjoyed ICO or Shadow of the Colossus will probably forgive any shortcomings that The Last Guardian may present (if any) and will be a game we can be satisfied with.
Source: Game Rant via VG 24/7, New Zealand Herald, The Guardian