It's just not possible for a civilization to make progress if everyone believes that the future will be worse and it's not possible to avoid it.
Climate change is a relatively straightforward problem with a somewhat-less-straightforward set of solutions. Whatever solution we choose, it will involve a group effort. Few people want to take on the costs of it while everyone else benefits. And it just so happens that one set of people, among the very largest polluters, deny that it's even happening -- in a variety of mutually contradictory ways. Their failure is obvious and overwhelming, and they are a minority of the world, but it's sufficient to derail progress worldwide.
That's why I'm pessimistic. I used to believe that anybody that far out of touch with reality must surely be booted out of power sooner or later. I've been proven wrong: they gain more power by the day. And that one belief comes with a constellation of similar false beliefs, mutually reinforced, and each participant goading the other to proclaim the falsehoods more loudly.
I'm sorry that means I'm contributing to the problem you're citing, but I've only seen it get worse in my lifetime. The upward progress of the world had so much momentum that it took a long time to turn around, but the exponential increase in insanity means I just can't see any way that it doesn't do so.
I try, nonetheless, to behave as if I were optimistic. I do make my own small contributions to progress. But I expect to see them all wiped away or made irrelevant.
I think you're going to be amazed at the changes that are coming, and how relatively painless they will be.
If we were more pessimistic, we would take preventative measures seriously.
“Everyone believes the future will be worse and it’s not possible to avoid it” is a strawman, I think.
I think a lot of people have given up.
Granted, the polls don’t measure apathy, but this doesn’t strike me as a society that is convinced climate change is a pressing problem. We’re more mildly concerned, and mildly supportive of policies aimed addressing it, even in a very limited way.
https://globalnews.ca/news/4811385/ottawas-unpublished-inter...
Net result - the hordes are still being idiots, and the rest of the world is blundering on thinking things ain't that bad/action isn't that urgent.
Last year ABC news gave more air time to the new royal baby in a single week than they gave to climate collapse in a year. You may feel inundated with pessimism, but that is far from universal. (Source: https://www.mediamatters.org/blog/2019/05/21/ABC-News-spent-...)
I think optimism/pessimism is the wrong axis for this. It should be complacency/activism. I think MLK’s Letter from Birmingham Jail is more apt than ever.
But I think you're right that complacency/activism is a good lense to view things through. The people that accept climate change is happening remain fairly complacent. Whether this is due to insufficient pessimism or complacency, the result is the same.