There is certainly no reason to be +40 and do "dumb work" - though "dumb work" is also an innovation agent to find or request APIs.
You have experience and can co-ordinate younger folks to do smart work which is an enabler for them to grow older faster... :-)
As long as they... ahem... we.. don't become grumpy, everyone can grow older faster and still stay young. Even wrinkles give you some authority and dignity... :-)
Cheers,
Julius