True, but almost every society expects its elders to still do some kind of work, usually house work and child care, which helps free the healthy adults to do the more difficult work. Those who can't do that are usually very close to death.
So then what is the complaint? They are indeed contributing to society. We enjoy the level of technological advancement that we do because our innovators are free to innovate, and not wasting their time on prosaic matters (because the elders cover that for them)
That is the normal human experience.
But also not what I'm suggesting.