Possibly age is relevant in the ability of a very mature human being to absorb the sudden unexpected increase in g caused by the suggested trim tab failure?
I was accustomed to flying aircraft where moderate to high g was a normal part of the day. But even with a g suit it was tiring, and I was in my 20's then. I am 50 now and would not want to put myself under that sort of stress now, let alone at 74!
May turn out not be related to this horrible accident. But I don't think you would find many people who are not surprised at the age of this man, given the stress of the sport of air racing.
O'Neill.