Hill of course understood that the Sons of the Earth were the most stubborn type.
It's not that they're all rigid old fossils who don't know how to adapt, it's that some things, even if they understand them and can see them clearly, they still don't want to do.
Like Aesces, who actually understood a lot under Snow Cloud Peak's constant nagging—when he felt that doing something was a betrayal of his allies, he just couldn't bring himself to do it.
Because Snow Cloud Peak is born aggressive, his starting point is often rather tough—he clearly believes that the best defense is offense.
So he might not be able to hit that point in Aesces' heart, and instead just keeps telling him how to fight back more effectively.
That was why Hill told him directly that any defensive measures set up to protect himself were not wrong.
You don't have to be the one to cheat people first, but you absolutely can't be completely undefended.
