you're not gonna see airline pilots suddenly dying in flight now because they raised the age by 5 years...give me a break. it might occasionally happen just like it did before they changed the rule.
I think if you look at insurance actuarial tables you'd find that more guys will keel over. Not necessarily at the yoke, but they will. What if the age was 40? How many guys would keel over at the yoke? How about age 70? 75? 90? There is some age where the average pilot isn't fit to fly the line anymore. (the bell curve. I know somebody will have a great story about an 80 yr old who is sharp as a tack blah blah, i'm talking general pilot population). Age 65 moves in that direction. There won't be guys keeling over every week, but you'd be an idiot to think that it will be the same as it has been with age 60.