Yes, the difference seem nearly non-existent on the basic level, but accounting for the games being built around a specific timing where people are in close proximity with single-digit frame counts to rely upon for moves connecting or not, doesn't it matter much more to the fighting game than a shooter or RTS, making even that tiny fraction of time even more important?
I don't think so. Fractions of a second make a huge difference in CS as well, for instance. Fire fights often come down to tiny fraction of a second differences in response time to an encounter. The most renowned Starcraft players often execute more than 300 actions per minute on average (that means they are making ~5 actions per second on average over the course of the game).
I'm not saying fighting games aren't reflex intensive as well; they clearly are. I just don't see how they are extra specially reflex intensive, if that's your point.