Pessimists can never be proven wrong. Their predictions are just delayed awhile, or they will latch on to some specific thing to prove their point. Optimists can have a similar problem although they are at least a lot more pleasant to be around and will typically work hard to keep improving things that they see need to be improved.
I have always been an advocate for nuance and realism. Anecdotes can be informative but are not necessarily trend setting. Trends can be informative but are not necessarily easily understandable or predictive.
The pessimist has the luxury of always dwelling in the negative. When the negative doesn't happen as much as they thought, they just shift that to further into the future. If they don't want to do that, they identify negative trends to focus on amidst the good.
Perhaps the pessimistic-optimistic split is secondary to our different experiences and
I tend to think it is far too exhausting and useless to be Chicken Little. It gets you nothing. If your fears are confirmed, you don't get a prize, you just get your worst fears confirmed and you can talk about how right you were. That and 25 cents can get you 10 minutes at a parking meter. Personally, I acknowledge the challenges and the difficulties, but work to make the future as good as I can. And I try to surround myself with people who feel the same way. Selfishness only goes so far, and the truly selfish usually end up the most miserable.
If I listened to some people on this forum 13 years ago, I wouldn't be in the greatest career I could have imagined, working with a great group of people, and getting paid well to do something I enjoy and have a talent for. But that being said, you do have to listen to all voices. Understand what you are doing, understand who you are and what you want, and always be prepared and vigilant. So I appreciate the naysayers on this forum as well as the optimists, although I have greater respect for the realists.