Well if you go by total extinction, then even Skynet in Terminator doesn't count given that there were people left over to resist.

I don't think it's impossible to upset the balance of value in a Mansa Musa kind of way that can lead to black death levels of destruction though resource misallocation. Unlikely, sure. But with the wrong kind of people in the wrong place? Could end up pretty bad. We've built our society as a great filter that funnels sociopaths and psychopaths to the very top by selecting for lack of empathy, and now it's primed and ready to bite us in the ass.