It was totally genocide.
Hydaelyn literally killed all of her people to make weaker more frail people, and then became the god of those people.

The funny part is the Zodiark plan seems to have fucking worked because it wasn't until we killed Zodarik that Metion started to attack Etheirys again.
Which means even in an incredibly sealed state, Zodiark was enough to scare Metion away.

Like I get this wasn't the developers intention with the events, and the takeway shouldn't be that Hydaelyn is an insane genocidal god, rather EW's story is pretty poorly written.