I think replacing Smash Ultimate Ganondorf is a big mistake. In a lineup full of irritating yet replaceable gimmicks, Ganondorf stands out as a pure expression of power. A well-played Ganon is terrifying and suffocating, menacingly creeping towards you to shut you down with lightning fast, bruiser aerials and closing in with terrifying deadly burst options from range. Smash Ganondorf is iconic and super fun to play as and against.
He is bad in high level competitive play. However, that doesn't need to be important – 95% of you don't play competitive play, so it's not a huge deal for you. His limitations might honestly be a good thing – one of the reasons Ganondorf is so hype and easy to root for is because, when you lose to him at high level play, you have no excuses. Ganondorf isn't cheesing you with some silly gimmick in the way guys like Lucario do (surprise i have 999 power now) or Incineroar does (hehe you attacked me and I used a frame 3 armored option to beat it, have fun taking 50 damage from my next attack). With losing to Ganon, you just got outplayed by a character with worse tools than you, so you have to live with the notion that Ganondorf didn't just secure a win, he dominated you on an emotional level. Isn't that perfect for the character of Ganondorf?
When I think of characters that have super unique or representative movesets, I think of Olimar, Mega Man, Min Min... not exactly an enviable group of fellows in terms of fun and/or game design, and not experiences I want to replicate. If people want a different kind of Ganondorf, I'm a little sympathetic, and it could be done well. But please make him a new character and don't wipe out the existing guy, who so many know and love, for a guy that will probably be less fun to play and less fun to play against.