Nice, I'll be borrowing this, if you don't mind.
I'm in my 50s, and while my body is definitely not as functional in a raw sense as it was 25 years ago, my overall satisfaction with life has never been higher. I know that over the next 30+ years my body will start to fail in more substantial ways, and if I'm unlucky, so will my mind. But that's fine. There's a whole lot of possible awesome between now and then. And even the 'then' will probably not be so bad as to negate the awesome of that time.
This is also why i love my old computer, my old scratched up cellphone, a beautiful old car that still runs fine, - the structural integrity of things that has served more than their purpose. I love them even more than "new things". It just feels good to use them on a visceral level.
It's a kind of mindfulness and appreciation for things like the beauty of the stone that has been rounded by the seawater over millennia, or your old trusty body that has more wrinkles but also works like biological magic if you really think about it.
Another iconic "older gentleman" i have met was a meditation teacher in his 80's in SF, still incredibly lucid, still thinking about science, reality dreams and meditation, experimenting pretty much everyday with "being alive" and sharing it with his community.
Cool people comes in all ages!
I know people who who's always had health issues and i have a grandmother who is 96, she loves her plants and her iPad, always tell me about all the books she's reading, the things she's seen on the internet, she cries with joy when she sees her grandkids and still sees her friends regularly. That's how diverse life is.
Your perspective is one of western youth supremacy, in many other cultures being older can be a privilege, you gain something, doors close but others open. That's how it's always been.