You don't stop living because you are growing older, you grow older because you stop living
This is rubbish. Age is not just a number.
Which does not mean you shouldn't live life to the full in old age.
It often means, though, that what you define as "to the full" in your sixties and seventies is a bit different from what it was, what it felt like, in your teens and twenties. A few lucky people might still be able to do all the things they could do in their teens and twenties when they are in their last few decades but in my experience and those of my peers, one actually does slow down a bit and get tired more easily. That's not stopping living (which is a silly phrase anyway).
People who don't accept that, in general, age makes a difference are deceiving themselves which, after covid's demonstrably greater effect on old people, is rather astonishing.