This is a good point. Optimism is good for motivation but it has to result in action and not be simply ignoring a problem. Pessimism paralyses people into inaction but by understanding the psychology we can change that.
I wrote a series of posts on this recently with more to come. Far more than I can fit in here. It's a classic tragedy of the commons but there is hope.
https://unop.uk/how-to-help-with-a-big-global-problem-as-a-t...