I wonder how many people comparing the ending to KH have actually played KH, because I don't really see the correlation.
There is nothing crazier in this ending than there was in the original FFVII, which I'd like to remind people is about the genetically engineered son of an alien trying to manipulate genetic copies of himself in order to crash a meteor into a planet where dead people literally become sentient gasoline in order to become a god while his amnesiac clone, two eco terrorists, the last surviving descendent of an ancient race of geomancers, a cowboy rocket scientist, a shapeshifting vampire, a ninja, a stuffed animal, and a talking cat-dog try to stop him, but are impeded by, basically, the Trump administration looking for the afterlife because they want to exploit its resources, and the planet creates biomechanical mecha to fight them. Oh and it has tankceratops, a tank that is also a triceratops.
The whispers are just a drop in the bucket.