Ok obviously not true for all games because some art style looks better in 60fps like Racers, side scrollers, futuristic games. But some games just look straight out better at 30fps, mostly due to the art style. If the art style is post apocalyptic, or Roman Empire or fantasy based, it just belongs in the more cinematic looking 30fps. For example I just got a PS4 and Killzone online at 60fps just looks totally different and not the Killzone I know of on PS3, just kills the whole art style.
So just here to say that 60fps is Not meant for every single game style despite what the tech guys and fanboys, especially PC gamers say. I believe that in the future when all hardware can run games at 60+ fps as a norm, 30fps will become an art filter and will modded/ added to games for the specific cinematic look.