The drone technologically is more advanced than the human brain.
But the information concerning what he was doing was not broadly available to his mind. That’s important, because he wasn’t able to control his behaviour in the light of all his beliefs. He responded automatically, without being able to ask himself whether he valued what he was doing.
A whole range of information which would normally have stopped him (screams, the sight of blood, his mother-in-law’s terrified face) couldn’t interact with the mechanisms causing his actions.
The Canadian court found Parks not guilty on the charge of murder (an acquittal later upheld by the Supreme Court). I think they were right to do so.
Neuroscience provides evidence that in the absence of consciousness, we can’t control our behaviour in the light of our values. And that’s a good reason to excuse us.