Why wouldn't older people say their age? Lying about it or pretending they are younger, certainly won't change anything.
I am darned proud of being such a healthy, active 63 year-old, and of having such a studly 65 year-old boyfriend/travel partner/husband. We plan to traipse around the world, exploring, playing, and burning miles and points for another, three decades or more.
Like others have said, however, there is so much to learn, that I doubt that even at the end, will we call ourselves experts.
IMHO, "Advanced" is having enough knowledge to always makes sure you sit in first (even on cheap tickets), getting upgraded to beautiful suites on a regular basis (even on cheap rates), and always having more miles, points and upgrades than you really need. You got that, and life is good. ^