There is no gameplay advantage. The option for 60FPS only affects the rendering of the environment and fighters, it does not effect gameplay FPS.
A user will have no significant advantage during gameplay other than it looking smoother. All gameplay inputs are still 30FPS.
Any gameplay advantage between 30FPS and 60FPS is in your head .

ちゃんと読んだのか？
見た目はヌルヌルになりますけど内部処理的には30fpsなので対戦には影響しないですよと言ってるようにしか見えないが