lol. It's okay. He's been saying this for like a month. He must really hate Marth.
I can't say I'd buy the man a drink.
But in all seriousness I do realize he's not a clone, and he is a stand-alone character with a unique moveset. I do think that all characters fitting that description (especially G&W, in case you couldn't already tell) should stay in the game.
How many FE games ago was Marth? I've never had the pleasure of playing them but from what I can gather Marth is pretty old school, whereas Roy is just Japan-exclusive. Counterpoint to that is Lucas, who is also Japan-exclusive but replaced Ness.
I've played enough Marthes in my time to realize that his removal, as well as Sheik's, would impact the competitive scene drastically. As a Falco player I have a very hard time getting close enough to decent Marthes to pull off anything but some annoying SHLing and maybe the occasional shine or pillar.
I hate Peaches more, though, but I'd cry if Peach wasn't in. Regardless of her whorish dress.
My point is that Marth returning isn't really as paramount as most people think, and I personally am exploiting that in hopes of him becoming an AT.