Age per se has little to do with it. Fitness, abilities, etc. have much more. I remember a woman who has done the occasional MR I went diving with in the BVI - she was scuba diving (solo) and doing some underwater video twice weekly - at age 85. Diving with Jack Randall at 78 at Midway - he could hardly wait to get back from diving two tanks so he could get a game of tennis in; exit row, no problem, he could probably teach some FAs a thing or two about it. Leni Riefenstahl - had to lie about her age ("downgraded" it to 70, as I think she was 80 when she got certified to dive.)

I know one 70-year old retired woman who does plenty of air travel and mileage runs, more than maintaining an AA EXP, and is quite able to operate an exit hatch. Of course, she is still young, so I shouldn't judge for a few years yet...

Now where I get fit to be fried is when a person gets early boarding because s/he "needs extra boarding assistance" and THEN sits in an exit row. Ya can't have it both ways... and s/he'd better not be MY impediment to speedy evacuation!