In regards to Geno and the Grinch Leak, here's some important takeaways:
-Grinch Leak basically forced Nintendo to acknowledge Geno's popularity. Let's face it, Isaac, Banjo, and Geno were basically what made it into such a megaton hoax.
-Shadow and Isaac were doomed from the start but Banjo was in his super early stages and obviously a huge secret while Geno was a JPEG. Geno probably was planned to be a Mii costume with Hero in the initial draft but, obviously, that didn't happen and Power of 6 theory helps provide a foundation for that.
-Geno is literally the only major character from the Grinch Leak that isn't playable or an AT a year later.
Again, my speculation, yadda yadda yadda, but it's kind of gotten hard to escape the shadow of the mountain of evidence and coincidences that Geno's eventually coming.