While the tremor thing might be a factor, it's by far not the main reasons why games need higher framerate. Games are fundamentally different from films for a

While the tremor thing might be a factor, it's by far not the main reasons why games need higher framerate. Games are fundamentally different from films for a simple fact: Games show reactions to your input, films are only consumed passively. This means for games it's not only important how the stuff on the screen looks and moves, but how much time passes between you pressing a button, and a thing moving. At 60 FPS that time is ~16 ms, which is almost unnoticable. At 30 FPS that time is ~32 ms, twice as long, and for people used to 60 FPS extremely noticable as a form of sluggishness on the controls. (Although for some games that have the gameplay with some inbuilt sluggishness that effect disappears, Dark Souls for example.)