Interesting! From a reader:
Jonah,
Thought you’d be interested to know there’s a scientific
term for what you’re describing: the uncanny valley. It was
first used to explain why robots who look only vaguely human
(like C3PO) can be endearing, while robots who look
substantially human BUT NOT QUITE are creepy. It’s assumed
that the “almostness” triggers some primal fear instinct in
our modern brains: “That’s not a human! It’s trying to fool
me!”
Here’s a link.