This is something developers seems unable to understand for the most part, but performance is more important than graphics. Graphics will not a badly performing game for long. A game that performs well not only looks but feels good.
I think 60fps is essential for platformers, fighters and action games. Just download the trial of Strider on PS3/360 and then compare to the one PS4/X1 versions. Its a worlds difference. A crappy game becomes a good game just like that.