The fear of the atomic bomb is relatively instant (at "best") or as bad as finding out you have cancer. if you die, you die. You won't even perceive the pain. if you don't die, you do your day-to-day until some sickness hits you from radiation and then die.

The fear of AI is one that does (and already has, in many cases) in fact change your day-to-day. And given how the increasing economic disparity is going, it will not be one that changes the day to day for most people for the better. No one is positive because the current societal rate of change for most people is negative.

AI is a catalyst and will only accelerate what is already happening (since it fundamentally does not create nor open up new forms of labor). So it's clear why people who feel their day-to-day will get worse are not optimistic.