Please correct me if I am wrong, but the way I read the OP was that negativity without reason is one part of the issue.
In your case of the car falling off a cliff, perhaps it is gratuitous negativity to say "We've just driven off a cliff! Lets open the door and get out of here!" but it's not gratuitous negativity to say "We've just driven off a cliff! Lets open the door and get out of here because this car is falling towards the ground at high speed due to gravity and motion and we're all about to die!"
I think if there is at least some reasoning shown with the negativity, the argument is more clear and others can learn from it.
Again, I could have misunderstood both the OP and your comment, if so I apologize.
In my experience, even when you describe the gravity and the impending impact, you are still seen as being negative. I think it has less to do with logic, and more to do with evolutionary biases. Mainly in-group/out-group bias (for instance nationality, or brand allegiance) or avoiding cognitive dissonance (If I accept your point, that means I have to change my view of the world to a more uncomfortable position).
In your case of the car falling off a cliff, perhaps it is gratuitous negativity to say "We've just driven off a cliff! Lets open the door and get out of here!" but it's not gratuitous negativity to say "We've just driven off a cliff! Lets open the door and get out of here because this car is falling towards the ground at high speed due to gravity and motion and we're all about to die!"
I think if there is at least some reasoning shown with the negativity, the argument is more clear and others can learn from it.
Again, I could have misunderstood both the OP and your comment, if so I apologize.