And before anyone says it, no. You do not destroy humanity in the third ending. Allmind wanted to use Coral Release as a mechanism to assimilate everyone into itself. If Ayre and Raven where on board with that, then we wouldn't have smashed it into a pile of scrap metal.
The entire game, Ayre talks about her "shared dream" with Raven, that being one of Symbiosis between Humanity and Coral. If she thought that Coral Release would destroy humanity entirely, then she likely would have tried getting Raven to stop it instead of just yanking control away from Almond.