You start helpless. You may end helpless. It is one of the arcs of a human life.
The arc is about autonomy.
I think.
If story is the underpinning, then you are a story and there is an arc. You may define your autonomy in terms of ‘what I can meaningfully achieve for myself as framed by the customs and traditions I was raised on’ or you may define it as self-will, which (candidly) never seems to play out quite as well as including others in your self-definition.
Part of the arc is your contribution to the lifestream – whether you have children, and your children have children. But it’s not the most important part. Everyone can make a contribution to the human family, it doesn’t have to be genetic.