It's more likely that the bulk of adults have stopped reasoning morally and instead go with socially prescribed conclusions. I mean, how else would you explain the killing if trillions of land animals each year?

Morality doesn't exist outside of "socially prescribed conclusions", it's actually a pure social thing, it has no other function, but to help individuals make socially acceptable choices.

That is a pretty bold proclamation. Still, the thought of killing and torturing an animal for your pleasure seems to violate ethics centered around reciprocity. You know, the old "do unto others...". Even if that rule is not based on something objective it still seems more axiomatic than, "Mmmm, they taste good therefore I have dominion."

kids can absolutely reason morally, they just don’t have all the scaffolding to support doing so well or coming to reasonable conclusions. kids even reason about the nature of the terms themselves (especially around christmas: “why do i have to be good? what does being good mean?”).

but the same five year old who is picking the 10 dogs over the 1 human is also grabbing their toy from their little sister and bopping her on the head with it and making her cry, so i am not trying to defend some notion of a developed sense of toddler morality.

Children can reason morally and do, they just didn't learn a lot of morals to reason with yet. Morals, i.e. what is good and what is bad, is something people never stop learning. Obviously learning moral values from cartoons isn't helping in situations with real people.