Mitch McConnell fell again today. Too proud to use a cane.
My Aunt Betty who just turned 99 yrs old at the end of September, was one of those 'too vain' to use a cane because it made her look 'old'.

However, with the assistance of my niece, her great niece, and the wonderful staff at the assisted living facility where we moved her last March, she has been bullied, cajoled, bribed, persuaded to finally use the cane. (Unless she thinks she can get away with not using it.

)
She is slowly becoming so frail she really would benefit from using a walker now, but nobody has had the nerve to approach her about that.
Evenso, age really is just a number. Aunt Betty is now showing signs of advancing dementia, but even a couple of years ago she was sharp as a tack with excellent recall and a strong sense of personal responsibility. It's heart breaking when the person that they were starts slipping away from us, but she has been my inspiration that it ain't over until it's over.
I know other 70, 80, and 90-yr-olds and one 104 when she finally succumbed to congestive heart failure who are brilliant or were right up to the end.
But for some, the time they really need to step down comes much earlier.
Years ago, I read and watched President Reagan's staffers assure the world that he was in possession of his faculties for his entire two terms. That was evident in his wit and humor expressed in his few public appearances after he left office. But those staffers admitted there were some signs of his developing Alzheimers that would eventually kill him. It was not enough to impair him in any important way though until years later.