Martial Arts instructors should thank the UFC for helping to put their training in perspective. Any illusion that training in a specific style would confer invincibility in mortal combat is just that, an illusion.
The best we can hope to learn by watching UFC is another insight into the psyche and technical facility of a combatant in very specific controlled situations.
This is ritualized combat with specific rules. The rules are meant to make the contests entertaining and sustainable. These are not fights to the death, those would look quite different.

Most if not all street fights have implicit rules too but they are very, very different from those of sports contests. Budo and chivalry are ancient names for rules of combat even in contests to the death.

As a 30 plus year practitioner of the Japanese martial art of Aikido, having also studied western boxing and European saber fencing, I am still a beginner in the art of learning about myself and my interaction with the bodies and emotions of my fellow humans. I was probably a better street fighter at 21 but now I have other skills which can bring to the contest.

It's fun to play "what if" but most people will thankfully never get to know how "good" they really are in a life and death situation.