As for environment degradation in general, just because prior predictions were wrong doesn't mean the biosphere isn't still headed in the wrong direction for sustainability. Maybe we have the right governance and economics to adapt in time, but that's not a guarantee.
Being positive about everything seems like a really privileged position. It also maintains the status quo. If you're Ukrainian, how positive would you feel about your country's future? How positive is Europe about NATO and it's future with the US right about now. How are Canadians feeling about their neighbor to the South? Are they confident future US elections will self-correct?
Maybe over the long term it all works itself out and human progress continues to the stars or whatever. Or maybe we're going to be part of a Great Filter intelligent species face because of short sightedness and powerful technologies they unleash. Or maybe we'll just muddle along with some gains and then losses. Civilizations rise and fall, we really don't know how positive the future will be.
There have always been wars and skirmishes around the world. Ukraine and Gaza are today's. There will be others tomorrow. Different tribes of humans just don't get along, never have.
If you think the environment is bad now, you should have seen it in the 1970s. Chemicals dumped everywhere, rivers on fire, cities choked in smog.
But the long term trend is always positive. Things are better now for more people than they ever have been.
We really don't know that democracy will always prevail, that capitalism is sustainable in the long term, and that our current global civilization is immune to collapse. We don't know there will never be a nuclear war or that climate change won't hit the wrong tipping point. We don't know that humanity's future will continue to be better off indefinitely.
Right. We don't. And we never did. What I was saying is that when I was young, there was plenty of reason to believe everything would go to hell soon... and we were wrong, things got a lot better. There's just no way to know.
The last Romans living in the Roman Empire in 400AD may have also concluded that their problems would eventually be solved and they would continue thriving, just like they had for a thousand years. But they would be wrong. Just go back to 100AD and they would be mostly right: they still had a good 300 years in front of them (so they would never see a collapse, nor their children and grandchildren).
So yeah, eventually things will undoubtedly take a very negative turn. The question really is, will that be in 10, 100 or 1000 years? You don't know, I don't know. But given the above , I think it's fair to conclude that by being positive you're almost always correct.
Getting older what I have realized is that the enthusiasm of the youth is born from the lack of experience, lack of responsibility, lack of anything to lose, and a position to really only gain from any changes. When you are young you are largely a spectator to the game, and just like any other game, your views will change when you become a player instead of an armchair expert.