>>45682901The term “Pokemon” was coined as a term to refer to literally any sapient creature that isn’t human after pokeballs were invented. They were designed to catch quite literally everything that is not a human, hence why it can catch literal gods, other-dimensional beings, and aliens.
In very ancient times, humans and non-humans were more or less equal. If humans wanted to tame something, they needed to contain it or attract it and domesticate it, just like how we did with ancient wolves and bovines and felines that became today’s dogs and cows and cats. Arceus, the god and creator of the world that the Pokemon series takes place in, wasn’t called a Pokemon until humans invented Pokeballs. In other words, it’s not a human, therefore, it can be caught in a Pokeball.
Alas, that’s my stupid headcanon anyway.