I would not exactly say so, but given how she was a Mary Sue, this game would have gotten nowhere with her around. You might recall the first scene in the game where Noirey is victorious, then gets tricked by the villain and puts Gamarket in danger. However, if it was Iris Heart in the cut scene, you can expect her to get back up, "punish" Noirey and then that would be it, so trickery from the villain (And even then, Iris Heart would "punish" that villain) would not have happened, and you'd have no story/game because Iris Heart would ruined anything that got the story going.
That, and also remember that this game is set in "Gamarket" different from "Gamindustri" so its simply a different dimension where Plutie (and even Candidates this time) do not exist.
[img] and [spoiler] tags work in the shoutbox - feel free to use them but please do not abuse this feature. If posting pictures please limit the height to 100 pixels or so (use [img height=##] tag). -Reimilia Scarlet