People in their fifties are sooooooooo old

Only, not. And people in their sixties, like the Rolling Stones*, can still rock out. Jagger can still dance, and his singing voice hasn't declined any (assuming you think there was something to decline) and the others can still play their instruments. Of course, they have displayed Elly's attitude towards retirement ("We're retiring -- okay, we're not retiring -- Okay, NOW we're retiring -- No wait, we're not retiring") but they don't have one foot in the grave, the way Elly, and John too, think they themselves have.

That said, I really don't want to see John shaking his thang to "Start Me Up".

*who just performed at the Super Bowl halftime, for those who are not watching or don't care about football.