BEagle, yes I agree totally with what you say there.
Jay and, I'm sure you are right about a sell-by date, but I expect that there will be other physiological factors that would make one unfit for the high-g, high-performance cockpit before G-tolerance in most cases. As pilots doing aeros probably don't go in a centrifuge every year (most probably ever) they're unlikely to be aware of when their g-tolerance starts to change. As BEgle says, this type of aeros isn't going to expose anyone to that much g anyway.
Also remember that that there are lots of other factors that are more likely to affect this: dehydration, fatigue, medication, minor illness among others. Most professionals, especially those with a fast jet background will have a pretty good understanding of these things.
Again, too early to try to apply any of these things to this accident. Rule nothing in, rule nothing out.