MMA is a sport.
Aikido has been around for thousands of years.
Today's MMA fighters are not magically tougher than every ancient martial artist or warrior
Getting angry, aggressive and running in trying to punch someone's head off only works in a ring, when life is not on the line, and no death strikes are allowed. Its like running into battle with your balls on your face. It's easy to beat someone up when they're not allowed to simply end you, and if you're sure they're not going to be using any environmental weapons or whatever they may be carrying. Masters of Aikido could take down Samurai