It isn't racist, it's realistic. If an entity thinks with something that we don't even call a brain, we shouldn't trust it because we have no way of knowing its motivations.

Yes, but it says "never trust", not "don't trust by default". It should be possible for non-brain-based beings to demonstrate their trustworthiness.

Edit: Also, you can't spell "REALISTIC" without "RACIST LIE". Proof by anagram. So there.