I think the ancestor drones are land and sea mines, or really any kind of trap that dislocates the timing and control of the "trigger" from the person who launched it into the environment. These newer drones have just gained locomotion instead of having to wait for victims to come to them.
Norbert Wiener’s cybernetics was based on automated killing — which he beautifully disavowed in peacetime [1]. Which historically is one of the main reasons we think about “Artificial Intelligence” instead of cybernetics (Wiener kind of pissed off the defense dept). [1] “A Scientist Rebels,” 1947 http://lanl-the-back-story.blogspot.com/2013/08/a-scientist-...
Cybernetics and artificial intelligence are two distinct fields, though? I have friends with degrees in both, it's not some long lost alternative name for AI (though we're unlikely to see something like Project Cybersyn using cybernetics today instead of some overly deep neural net).