Super Smash Bros Ultimate story has Kirby being the only surviving character against the hand. This leaves you to use the warrior of dreams to set the others free. While many figured his survival was because Sakurai favors him the creator himself says that is not the case. You can see what he says below to see if you believe him or not.
“Some of you may have forgotten, but Kirby’s Warp Star has been able to, y’know, warp since his very first game.That alone made him a pretty solid contender. The only other two fighters that could have survived would have been Bayonetta or Palutena.”
There is more reasoning by the way.
[Kirby was eventually chosen over Bayonetta and Palutena because Kirby was seen as an easier starter character. The perception is that Bayonetta and Palutena have more of a learning curve to them when compared to Kirby’s basic play style.
Notably, Kirby is a combatant that has been present since the very beginning. This means that he’ll feel familiar to veteran players. By design, Kirby is a well-rounded character that doesn’t necessarily have to be played a specific way — unlike Bayonetta and Palutena.
Sakurai also specifically mentions that just because a character has access to a teleport, it doesn’t mean they’d be able to escape Galeem. Mewtwo or Zelda’s teleport, for example, is merely short-ranged.
Kirby, however, has access to the Warp Star. Thanks to its ability to warp, it breaks the law of physics, according to Sakurai.
Of course, this adventure mode isn’t going to just star Kirby. It doesn’t take very long before you are able to unlock the next fighter for your team — Mario.]
As always thank you for reading.