I know you were being sarcastic but you might be accidentally right. Have you seen the level of fear mongering in politics and a lack of regard for the future from the eras when they existed? I think the nuclear bomb drills may have really ruined them - that or the leaded gasoline.The 'I turned out just fine insistence' is often seen from people who support beating the pattern of abuse in beating their children.

I'm not trying to be a snide jackass here - I suspect it had real deleterious effects but they were normalized and went uncommented upon. The Black Death appeared to have some similar precedent as western culture became utterly desensitized to skeletons and 'the end is nigh' beliefs became a sizeable reoccurring minority to majority. I believe Rome had similar beliefs as some saw the writing on the wall of their decline. I'm not an expert but I wouldn't be surprised it died out in the dark ages as people were in the actual 'post apocalypse' and doing things like former Roman seamen founding Venice.