60fps don't make games more enjoyable (1), as well, just like 30fps, it's a random lock number (2).
Games should be built with what they want to focus in mind and follow it, that's about it, sacrificing anything to hit that illusory enjoyment wall is nonsense, as is for resolution.
Games should be build to deliver what they are meant to deliver as a game, sacrificing something to hit numbers on a paper is the mentallity that should be sacrificed.
(1) Yes, it does. Playing a game like Burnout, F-zero, Any classic arena FPS on 30fps is a completely different experience. Even take classic games like Mario 64 and Tekken 3, PAL version (30fps) vs JAP version (60fps) is a completely different experience.
(2) No, it isn't. The 30fps "lock" is not arbitrary, the number is specifically meant to be synchronized with a standard TV image refersh rate (60hz) without altering the pace of the game or skipping frames.
I can agree games shound be build to deliver what is originally envisioned by the developer, but the framerate target should be a part of that vision.