I feel that people are making the statement a little too broad when it comes to “hype levels”.
For instance, let’s say Geno and Isaac are the last ones. They wouldn’t be well known to the casual fan base, but the hardcore fanbase will go crazy with them, even if they’re highly popular during the ballot, it only reach 1.8 million, about a sixth of the people who bought the Smash 4. The hype for the general audience is that Everyone is here, while the more hardcore fans are still pushing for their less known favorites.
That’s why I get a little agitated when people get Shulk in the mix. Shulk wasn’t that hype to the more general audience who may not have known him, but I feel that it’s dismissing the fact that the more hardcore fans (i.e. here) definitely were and they were supporting for his inclusion. Sakurai even said that the reason Shulk got added was because he had a large amount of support from Japan at the time.
A similar thing is the case for Isaac, Geno. They aren’t well known to the general audience, but definitely are pushed by the hardcore fans, and thus hype to them. Some characters like Elma, and a Rhythm Heaven character also have a lot fans, the former having a lot of support recently.
Are they less hype than King K. Rool and Ridley. Maybe Isaac and Geno are on the same level, but otherwise, yeah I’m not going to deny that. But there are potential last reveals that aren’t rock bottom than what people seem to make them out to be. Even the Sun and Moon Pokémon, either be it Decidueye, Incineroar, or Lycanroc have a lot of fans for that would be stoked for them as well.
Not to mention the fact that the team are on a more tight schedule than last time to reveal content, something like this can very well happen.