Not all libertarians are in an affectative death spiral, obvious or otherwise. It's true that many are, but I, for example, recognize tragedy of the commons scenarios and accept that some regulation can be useful to mitigate these problems. I believe there are some specific legitimate purposes of government, such as outlawing aggression, internalizing costs, and coordination (e.g., everyone drives on the right side of road, it would have worked for everyone to drive on the left, but as a society we had to pick one and go with it). Further, I think that every law should be validated to be achieving such an objective with minimal intervention.

I understand how you can form this view, seeing all the pro-business conservatives seizing on libertarian rhetoric to oppose regulation, but then neglecting the responsibility part when they want subsidies, or all the people who correctly notice that most laws are counterproductive and then incorrectly conclude that all laws are counterproductive. But when you claim that all advocates of libertarianism are like that, you are attacking a strawman.

I would have a much easier time taking libertarianism seriously if its advocates weren't all in obvious affective death spirals.

This kind of absurdly absolutist statement achieves nothing but display personal animus toward an ideology. It is true that many libertarians are in death spirals, but I know of no political group that does not have large numbers of supporters in Affective Death Spirals. In case you were unaware, this is a universal tendency for idea-based groups.

And politics is the mind-killer, no matter your politics.

I agree with this, though:

Libertarianism does not handle tragedy of the commons scenarios well at all, and that's exactly what most existential risks are.