IMHO, that sounds just like a burnout from activism, caused by cynical people who are "meh" about the issue.
Logically, your claim (that catastrophizing drives people away from activism) doesn't make much sense. If you still think that environment has same value as you did in the past, then you should still support the ecological policies, regardless what people are saying. If you only supported them because of catastrophism and not because you don't inherently value it, then you were misled and shouldn't have advocated it in the first place.
What I am saying is you have moral agency, and if you feel misled by other people's factual claims (e.g. exaggerating the impact, regardless of reason), it shouldn't change the validity of your moral stance or your values. But if your values didn't change, you're still an advocate, although perhaps with a different outlook.
The problem is the doomsday prophesies are unfalsifiable. We are at the point now where questioning anything related to global warming is professional suicide. Experts have been telling us perpetually that “soon” we will be past the point of no return and we are doomed. The climate is so large, and so much data is collected, and experiments are impossible to conduct, that you can make a case for almost anything at no one can say you are wrong.
I find the whole thing very exhausting. Fine let’s reduce carbon but I’m not going to live my life in panic and depression because of this.
Logically, your claim (that catastrophizing drives people away from activism) doesn't make much sense. If you still think that environment has same value as you did in the past, then you should still support the ecological policies, regardless what people are saying. If you only supported them because of catastrophism and not because you don't inherently value it, then you were misled and shouldn't have advocated it in the first place.
What I am saying is you have moral agency, and if you feel misled by other people's factual claims (e.g. exaggerating the impact, regardless of reason), it shouldn't change the validity of your moral stance or your values. But if your values didn't change, you're still an advocate, although perhaps with a different outlook.