Honestly, as much as I, like most of us, bought into the hype, in a General direct, Shantae doesn't make nearly as much sense as someone as Isabelle. looking back
A general direct reveal, or at least an ideal one, should be one that might pull in people who weren't super interested in the game.
Shantae's install base, while dedicated, isn't really large enough that the non-crossover area between it and Smash would be huge.
Animal Crossing however, has a HUGE install base, many of which are more casual gamers, that are very dedicated to the game and the characters, especially Isabelle.
It's the same reason I feel like Isaac and Geno wouldn't have been good here, in hindsight. I feel both of them and Shantae would suit a Smash direct MUCH better.
So to me, this isn't a "well, that was our opportunity, game over," it's a "Hmm, this just wasn't the right day" and I am just as sure she is in the game in some aspect as I was yesterday. This has no bearing on us at all.