The best comparable would be the first big computer disaster or the first big internet disaster. Do we have consensus on what that would be?
There are also cases of airplane crashes due to software defects, blackouts, critical hospital failures, etc. I suspect the first "AI disaster" will be pretty similar: a sudden and undetected drop in software quality with life-threatening consequences. (Doesn't help that the author of the post blithely asserted that programmer-agents is a solved problem, when it very much is not). But I could see an LLM doctor/etc causing a very different kind of disaster.