In case anyone missed the latest reveal
Not counting 64, Luigi has never been a clone of Mario.
From top of my head:
In Melee he shared animations for neutral and down bs, throws and some smash attacks with Mario/Doc Mario.
In Brawl he shares even less.
Even if he shared animations in Melee most of WeeGees attacks had differences in mechanics.
In 64 he was inferior 100% clone.
In brawl IIRC:
Luigi has negative friction, meaning he actually slides rather than comes to a stop. Only character with this feature.
Luigi's up special has a sweet spot unlike Mario's, which enable KO potential.
Luigi's side special is a charged up explosion, which is a horizontal recovery move. Mario has a cape which changes both direction and directional acceleration of projectiles and characters.
Luigi's Down Special I'm forgetting, I think it was use to be his down aerial? Mario has his F.L.U.D.D which is a 0 damage direction influence device used for edgeguarding.
Luigi's Dash Attack is a multi hit multiple punch attack whereas Mario has a sweep kick from soccer.
Luigi's down taunt is an easter egg that actually meteor smash if another player cliff-grabbing.
So that's just off the top of my head, outside of height weight jump speed and other variables that make them very un-clone like.
Personally: I'd rather see more discrepancies between Ganondorf and Captain Falcon. An incorporation of Ganon's twin swords for increase range to make up for his abysmal speed and recovery