I think it's always combination of many things, which make it harder to retrace.

a good bit of it is due to some remnant of a trait that was once evolutionarily advantageous and is now hardwired into our brains.

That was exactly what i was thinking of. For example 5000 years ago, while hunting for food, a small mistake could have ended killing someone or loosing the precious meat they needed badly to survive. And we have a longer history in living like that, which every mistake could result in serious damages, than living how we live now, that many mistakes don't have dramatic consequences. (or maybe they have great consequences but we don't realize it as fast as before).