If our brains evolved to be protected against man-in-the-middle attacks, that would be extremely scary because it would imply the proto-humans that didn't have this ability went extinct to some brain-invading predator!
If we go far enough back, we may have done common ancestor/s that did develop compensatory mechanism/s to at least somewhat mitigate specific kinds of attacks, like what tarantula hawks can do to tarantulas.
Imagine this to be the very reason the human mind is mostly self-illegible — that the birth of the inscrutable unconscious was a defense mechanism?
Unconscious behaviors are often conserved across species and (lower level brain behaviors) in functionally and evolutionarily similar parts of the brain.