The theme exists in both One Piece and Naruto, but is executed much differently:
In Naruto, the theme is stated early, and spun with the idea that each generation should surpass the last. However, like Seafarer said, this got completely lost as the story went on, never quite surpassing what it achieved during the Hidan/Kakuzu arc.
In One Piece, the theme of inherited will is also stated early, but not exactly crystallized until the Enies Lobby arc. The way the theme is spun by One Piece is not that a generation is outright greater or stronger, but that people from the past had dreams, and those dreams carry on with the present. You see this theme appear "somewhat" in Naruto, but almost every major flashback from Romance Dawn to Dressrosa articulates this idea in a consistent manner.
tl; dr - Both works have a shared theme, but One Piece spins it in a way that's consistent. Naruto doesn't.