The phrase I used was actually “extinction scenario” rather than a singular event, and “most people die immediately, an unlucky few eke out lives of unspeakable horror and pestilence for a handful of generations before the species collapses entirely” was basically what I had in mind.

Really though I can’t imagine what you think this pedantic obsession with whether or not everyone gets blown up immediately is adding to the conversation.

It’s not pedantic, it’s referencing actual studies on the topic. No expert thinks that humans would go extinct.