Well he wouldn't, would he? If the DK leaker is to be believed, and he seems credible, Sakurai was oblivious to the demand of K. Rool pre-ballot. And if he said anything post-ballot, that would've been a tinder to the forest of kindling that is the Smash fanbase, lol.
Similar kinda thing could be going on with Isaac for all we know.
It wouldn't be Smash speculation if the Isaac fans didn't get dragged through the weeds until the very end when we get an (often unsatisfying) answer.
I'm happy the method of inclusion is being shaken up from the Smash 4 style of "who's done something recently?". Some people seem to be having a hard time of letting that mentality go though, hence some of the dissent against... well... K. Rool, Isaac and Geno. Funny because that whole recency bent only got kicked up with Smash 4. Anyone from the Brawl era can tell you there was much much less of "x just got a game, x must be getting in".
Fwiw that top image you posted is recent polls, not ballot-era.