YoRHa Alliance raid theory

[Hakuro89]

Makes sense to me, considering in the Automata world humanity had been extinct for millennia . To YorHa we could be relics of the past flung into their time, the future, thousands of years later.
As far as one of them becoming a WoL to protect their own world, there really isn't much of anything left to protect. Just the survivors of the resistance and whatever docile machines remain, especially if it picks up after ending E (the "true" ending).