I don't think that oversimplifying is going to help anything. Heart attacks are not always attributed to a person's weight. A person's weight isn't necessarily attributed to cheeseburgers.
I dive with a number of "People of Size" (Egads, Political Correctness is getting out of hand) In the water they are just as graceful as anyone else (remember buoyancy) That's not to say that there are some folks who would probably be better off sticking to Rec. diving but that's a whole can of worms in of itself.
I think what can be learned from the recent tragedy on the Algol, is that we ALL need to look out for one another. Yes, there absolutely needs to be a large degree of personal responsibility from each individual diver, but it is also is the responsibility of everyone present to stop someone if it looks like there are any signs of impending trouble.
Granted, This particular gentleman could have dropped anywhere at any time. Any one of us can. I don't know if he was exhibiting any signs of stress before entering the water, but as was said above, he had trouble swimming to the line. It sounds like this particular case was one which probably could not have been easily avoided. If he wasn't feeling well before the dive, he may have hid it well. Who knows?
This type of accident does appear to be on the rise however. There are too many people getting into deep wreck diving because it feeds their ego. That is obviously the wrong reason to start. Unfortuneately, there are those out there who will happily take their money without caring if the particular person should really be engaged in that particular activity.
We can joke all we want about "Darwin Award" candidates and so forth, but the sad truth is that there are people who just don't understand the risks involved. It is up to the rest of us to remind them that the only thing that happens fast in this sport is disaster.
I no longer do this type of diving simply because it plays too much to my competitive nature. I never was very good at resisting peer pressure. And there is a LOT of peer pressure and tough-guy attitude in many Tec. circles. If you don't believe me, then read "The Last Dive" by Bernie Choudhoury. So, I walked away from that aspect of the sport and stayed with teaching Rec. My wife and daughter are happier for it.