[Mithalwen]

I think it is the symbolic passing of the torch and the focus is on Elrond since as father and foster father of Arwen and Aragorn he is the most significant figure from Gondor's perspective. Also he was witness to the major events that ended the previous ages He reached adulthood about the end of the first age and would have witnessed the war of wrath, then witnessed the interim overthrow of Sauron and took up the responsibility if not the title of Gil-galad. Then with the destruction of the ring his task is done