The problem with doom is that it really runs the risk of demotivation. In that way, it's effectively like denialism.

Of course doomers are not a monolith and there are plenty of good people who understand how bad it is yet still care about mitigation and adaptation. I'm just not going to assume they're the norm. (I know plenty of people who think civilization is collapsing and are happy to sit back and watch it happen.)

The most important signal can get lost in the noise, and it appears at the end of your terminal man analogy, almost as a throwaway line: that we need to "figure out how to minimize the damage."

This is the critical part. All our emphasis needs to be here. We're shaping the zeitgeist, and while we ought to be honest and frank about likely consequences of overshoot, mitigation efforts should be the biggest, loudest voice and movement, so that indeed we can "minimize the damage," for ourselves and for the myriad species we're taking with us.