I think that 'normal' triathlon, including Iron Man (maybe especially Iron Man) is an endurance sport, not a technical skill sport. Rough sea swim, plus downhill MTB, plus trail run would be a different kind of tri. For 'normal' endurance amateur athletes that swim in lakes, ride and run on roads, something as technically difficult as swimming in rough surf should be called off. It is not something that most participants have trained for (or want, even).