Legacy and One Piece

Even though the manga has been around since 1997, One Piece is still active. Eiichiro Oda, the writer, has hinted possible endings in the past. However, he seems to continually extend the timeline of the story. Other popular manga that originated around the same time have long since ended; for example, Naruto, Hunter x Hunter, and Bleach. But, that is not the case for One Piece. The writer can discuss whether or not the decision to keep this manga going has damaged the storyline. Some speculate that the writer has the ending written already and he is simply filling in the gaps. Does the manga's continued popularity show that it has become living Oda's legacy?