Now I know you may have some questions, so here's a list I've come up with to explain exactly who will hate this character and why the salt would be legendary.
1: This is Mallow from Super Mario RPG.
a: He's ANOTHER Mario rep, so those people who want more series represented will be mad.
b: He's also the only original party member besides the one and only Geno, so they will be eternally ass shattered this boy got in sooner than their golden calf.
2: Look at 'em. He's a puffball. Because he's a cloud.
a: In lore, he's a crybaby softy that more or less gets declared prince because of his parents being royalty. Combined with the appearance, this gives off the impression that this character's inclusion is for children while being from a game no kids under 15 have probably played- also pissing off people like that 4chan mod that claims smash is an 'international culture event' or whatever they use to jsutify playing baby's first fighting game.
b: same reason why people hate Jigglypuff and Kirby. He's not 'cool' like Captain Falcon or Sephiroth, so there's some salt.
3: He's a boy. Not a trans, not a woman, a boy. People that want more women in smash BTFO. (Also in lore his parents are almost dethroned by a woman so bonus points if anyone brings that up to them that it was 'her turn' but I'm grasping at that point)
4: Cloud, small... Clearly he'd be a floaty flier, and with magic in game to boot.
a: Potential zoning character, potential for salt akin to Min Min or Meta Knight.
b: Froggie stick (a weapon he can use) can act like a sword in practice. Sword user haters mad because they're gonna be.
c: He could also use cymbals in both SMRPG and this game. People will bitch about the noise guaranteed.
d: Like Jigglypuff's rest, due to the floating, his up special may not be a recovery. Instead, Mallow has this quirk in the SMRPG games of using weather to fight. One ability is to
summon a cloud to heal himself or others. Do I need to describe what happens when a zoning character that's floaty can heal themselves from their danger zone between their opponents stocks?
5: And most importantly, the 'influencers' who react to Smash reveals will be confused. And because NO ONE is pouring out in support of this guy, every single person watching the reactor's lukewarm opinion of Mallow will lead to everyone saying he's a wasted slot like with Byleth or Incineroar.
Thank you for reading my TEDTalk about the Theory of Smash Salt, I spent way too long just writing this so I hope I provided some insight as to why this literally who is best pick for Smash Ultimate.