They might be wrong. And since they might be, and we have a chance to mitigate things somewhat, doom is not a useful response. It is paralysing.

Imagine fighting a war. If you and your fellow troops believe you will definitely lose, what happens to morale and the outcome? Morale collapses and you create a self-fulfilling prophecy.

The situation is serious but extreme doom predictions are the outlier in all credible models.