You know, with that response, I have to almost wonder if they didn't just give us an open door for something to consider. Either currently or in the future.

As he said, are children born in space by parents from Earth, considered Earthlings? So, current generations of some creatures we find, or even possibly, Beastmen, could have at one time been not of our world at all, but have migrated and settled in ours and through reproduction across many generations adapted and altered themselves to where they inhabit (the way the Ixal did regarding the loss of their feathers)

Do we really have an actual knowledge of where exactly the Beastmen come from? In particular, Goblins?