There's a lot of reasons for this - sure, gloves make a difference, especially to the intricate hand positions of some Kung Fu styles, and rules make a difference too, but the first few UFCs didn't have many rules and the results were largely the same as later events. Frankly, a lot of the so-called deadly martial arts represented in the cage weren't being trained in a realistic way. People thought cleverness and secret knowledge could supplant physical conditioning. This worked well for Jiu Jitsu, because it was so unfamiliar to your average fighter at the time, but not so well for striking arts. It's not that the traditional striking techniques were bad (although that can also be the case) it's that the training had strayed so far away from actual fighting that it had become almost irrelevant.
One of the early pioneers of modern MMA (and Pancrase as it was known then) was Bas Rutten, who has remained a popular MMA commentator because of his larger than life personality and detailed knowledge of the martial arts.
He's probably best known for dropping opponents with his liver punch, but that's just one of the tricks in his bag of whoop-ass. Bas recently posted a video on Facebook of him teaching one of his favorite ways to knock out an opponent. He calls it the "clothesline". It's a technique where you swing your whole arm at the opponents head, hitting with the forearm.
You probably have seen it used a lot in MMA - heavyweight UFC fighter Roy Nelson (who, coincidentally also trains in Kung Fu) is a big fan of it. The best example of his use of it was when he fought Cheik Kongo at UFC 159. The interesting thing, to me, is that this technique is not new at all - it has a long history in Kung Fu styles - you see it in Long Fist, but it's in Choy Lee Fut that you find its best representation, where it is known as Sao Choy or 'Sweeping fist'. Choy Lee Fut is a popular style in Hong Kong. It uses a lot of these swinging-arm style techniques, combined with very straight, stabbing, leopard fist strikes.
It's a very dynamic martial art. You might think these long range, circular techniques are slow in use, compared to a boxer's jab, but when they're coming at you, they're surprisingly fast. Here's a video of myself using Sao Choy in sparring, just to show that I do have some idea about what I'm talking about.
Image credit: The Irish Times
The resurgence of traditional techniques in MMA doesn't end there, of course. One of the most popular MMA fighters at the moment is Connor McGregor, who has brought a lot of the older Taekwondo kicking techniques back to the Octagon. Jiu Jitsu was always traditional, and that hasn't gone away, but fighters like Ronda Rousey have shown that Judo can be equally effective in MMA. To return to my original point though - it's not that the traditional techniques are ineffective, what needs to change is the training method. In the last UFC, for example, Stephen 'Wonderboy' Thompson demolished previous Welterweight titleholder, Johny Hendricks, using techniques that wouldn't be out of place in a Karate tournament.
The future's bright for traditional martial arts, and as time goes on we can expect to see many more 'old' techniques re-emerge in this most modern of venues.
Thanks for checking this post out! Graham Barlow is a Yang style Tai Chi Chuan teacher and BJJ practitioner based in the UK. He runs an awesome blog called The Taichi Notebook aiming to provide quality information on martial arts in general and specifically the arts he practices: Tai Chi Chuan, XingYi, and Brazilian Jiu Jitsu.