Talked about it a little bit in the Waluigi thread but I think people grossly underrate the significance of longevity in Smash.
https://m.youtube.com/watch?v=qLM2nMWsKL8&t=4s
This video sums it up perfectly for Ridley. Perfect attendance but always managed to miss the boat. Daisy and K. Rool were pretty much the same starting with Melee. Again, ignore at your own peril but Waluigi has missed the boat since Melee too but I'm going to make this about Geno. The starting place of this conversation really ought to be the first game.
The original Smash was basically a passion project between two best friends, Iwata and Sakurai. They did a lot of stuff without permission to get the prototype ready to impress Nintendo's executives with. They were impressed... To a point. The original was pretty low budget and it shows. For reasons unknown, Nintendo had very little faith in it so basically challenged Sakurai and Iwata to prove their goofy little project was worth it. Obviously, the original blew away expectations and was an instant phenomenon. Now Nintendo cared and wanted Smash as a launch title for the GameCube.
Sakurai basically had less than a year to churn out Melee. Nintendo basically gave Sakurai whatever he needed for the project. This is when the doors swung open and why Melee is basically the "first" Smash game. It was no longer a goofy beat em up, it was a celebration of Nintendo's, even the super obscure stuff. Melee's content crushed the original's in every aspect and that's basically been the standard since.
Melee was basically the start of things and fans were already dreaming big dreams. In 2000, there was absolutely no indication that Smash would ever have third party characters and yet people still asked for them. Again, Geno and Crash were two of them. There was absolutely no reason to expect these characters at the time but people did it anyways. The fans wanted Smash to be even bigger even before Nintendo itself knew it.
Brawl took things up even higher. Cinematics, third party characters, a sprawling soundtrack, an absurd amount of collectibles, bosses, assist trophies, etc. Basically made the game as if it would be his very last and more or less said this over and over again throughout development. This is why Sakurai's comments on Geno in 2016 are so significant. If this really was going to be Sakurai's last Smash game, he wanted Geno in there. That's deep.
Smash 4 raised things even higher and basically kicked the door off the hinges for third party content. Now Smash was a celebration of gaming. By Smash 4's end, third party franchises represented was in double digits. Again, this ongoing theme of trying to outdo himself, even in the face of personal injury. Yet again, Sakurai said he wanted Geno present in some form. Nintendo's biggest crossover at the time and Geno being there was important. Even in his Mii costume reveal, Sakurai basically described how they went out of their way to have Geno included somehow. He was the only Square Enix content that wasn't Final Fantasy. Those are some pretty big implications.
Now we're at the present. Sakurai has said over and over again that Ultimate is a tribute to Iwata, not only his best friend and mentor but the guy that pulled a ton of strings and snuck past forests of red tape to make Smash even possible. This is where we pull back some and look at Smash history as a whole. Geno has pretty much been there the entire time. He was requested for Melee. He had an honest effort to get him into Brawl. He got a Mii costume in Smash 4 through compromise. He was in the base game of Ultimate. The depth of the history is astounding and, to be totally blunt, Waluigi is the only other character that has this much of a historical tie to the entire history of Smash that isn't playable yet. If you want to ignore all the rumors and all the insider stuff, this is the strongest argument to why, if these really are the last 6 to 7 characters for Ultimate, Geno will definitely be one of them.
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