>>57013498NTA but your headcanon for humans isn't any more real than mine, we'll never actually be able to know and I'm fine with that. Personally I like having a bit of mystery regarding big concepts like that, because whichever is the "real" canon doesn't really matters. What matters is what each character in-universe individually believes and whether that affects them at all.
I'm happy to deliberately keep things like that vague for the sake of collaboration. There's evidence for and against there ever being humans in human for in the PMD universe. But at the end of the day, I don't care all that much.