Part of it is that I never was a fan of Tetsuya Nomura, given how he takes forever and a day to make something that requires diagrams to understand what is going on. In fact, one of the reasons why I consider Final Fantasy XV to be one of the best games in the series was became Nomura was removed from the project, allowing them time to actually finish the story. In fact, people had to get on him in order to make the KH games more accessible to people, such as how he only wanted HIS Final Fantasy characters in the series and was why Setzer got in.
You didn't know. But, there's a small amount of characters that would make me furious if they got in before Isaac, because their inclusion would make Isaac's chances worse.
Smashmar2
He's been featured without Disney characters in Therarhythm & World of Final Fantasy, but the problem is that if he's in the game, there is that chance Disney characters show up, and it's that element that makes me hesitant on his existence in Smash Bros.. Cloud getting involved actually helped out his role in Nintendo consoles as his actual game will be released on the Switch, so I retroactively forgive the rule he broke, but I just can't fathom Sora being in. He'd be just as bad as Goku, because while not a blatant violation, he could be the Trojan horse.