Optimism is a must, I agree. But it should not stop us from searching for ways forward, it should not make us complacent, it should not limit the actions we could take.
You want to believe. I get it. I was there myself. But then you'll open your eyes, see that all that progress is just words and smoke and you'll stand on the corner with the sign: "the end is nigh".
<https://www.chrismadden.co.uk/cartoon-gallery/the-end-is-nig...>
Some links for complementing your viewpoint.
Protected areas:
<https://www.ecowatch.com/earth-environmental-protection-area...> How Much of Earth Is Currently Protected? - 17% land, 6% sea, "many protected and conserved areas are not demonstrating effectiveness"
Fish farming:
<https://en.wikipedia.org/wiki/Fish_farming#Issues> Fish farming - issues <https://en.wikipedia.org/wiki/Seaspiracy> Seaspiracy
Hardwood:
<https://en.wikipedia.org/wiki/Deforestation#Present-day> - (... in 2019 ...) a third of that loss, 3.8 million hectares, occurred within humid tropical primary forests, areas of mature rainforest that are especially important for biodiversity and carbon storage. That's the equivalent of losing an area of primary forest the size of a football pitch every six seconds
There is no alternative. Defeat and death are not an alternative to working harder. It is infinitely better to fail while having tried to overcome than it is to concede defeat, give up, and lay down. The former is noble, and the latter cannot, and should not, be countenanced.
Join the fight. I am right now today building machines that grow more food on the same land. It's my day job. We don't have to work on adtech and digital casinos. We can win, we can have fun doing it, and we can be prosperous and happy.
You seem like you don't accept that nature is already critically depleted, that biodiversity is severely threatened (or you simply don't see its value), and that we're doing (as a species) too little too late too reluctantly to change the current "business as usual" approach to solving this problem.
I accept that I can't change your viewpoint here & now.
P.S. being alarmed is not hysteria, an opposite to optimism, or even defeatism.
We won't pave all the forests. We won't kill all the bugs. We won't net all the fish. Partially because of hysterical people such as yourself, which is sometimes useful, and partially because of cold-thinking people such as myself, which is also sometimes useful.
For example, more than a few countries protect more than a quarter of their land. You've heard of national parks, I'm sure. Where I live, 32% of the country is protected, and of course, not all unprotected land has been paved.
The fisheries, too, are protected to varying extents, and so we farm fish in sea-pens and ponds inland. There's work still to do to rebuild the fisheries to their former glory, but it's not being ignored and pillaged as you imply. The fisheries are doing well and improving here and elsewhere, and fish is relatively affordable for hungry human beings.
What we did 100 years ago, we have learned from, and stopped, we won't clearcut the rest of the old-growth, in fact we have replanted, not just pine, but also hardwoods, even some very slow growing ones, and we hope that in a millenium (it takes a while to grow), we will have more of our old forests back.
Not much furniture is made of hardwoods now, and not many farmers in the developed world slash and burn. We already have made great strides toward making our dominion stable; perhaps even a net benefit. Pine farms sequester a lot of carbon. Keep in mind that there is no such thing as the "undeveloped" world, only the "developing" world, so they'll get there eventually too. We can and should have it all.
I take it that you personally do not live in the wild forests alone and naked? You also partake of this glorious civilization we have built? Why? Because it's better. They cut down trees to build your house, and I think you'll agree that it was a good idea so that you don't have to live in the rain. We don't have to pave it all, but we do have to pave some of it.
I will not divest myself of sympathy for the hungry men, women, and children of the world because a sanctimonious actor who can spend $1000 on every meal insists that his ideology is superior to mine. Sanctimony is never convincing.
Nevertheless, all the meat here is grass-fed, and all the cows look happy. I see them when I'm driving around. They hang out in lush meadows and on hillsides. In fact, where I work, there are quite a few grassy hills that do nothing, so they graze cows on them part of the year. It's nice to see them trampling around and playing while I write machine control code. Those cows are going to die one day anyway, we may as well humanely make meat of them and stay strong and healthy so we can build a more beautiful, prosperous, peaceful world.
In closing, I will say that I know the above is a little optimistic, but a little optimism is called for to move us forward. We need not depress all of the kids who will build our glorious future with a gnashing of teeth about the wrongs of the past, with claims of defeat, but to motivate them with possibility. We can do better, sure, and we are trying. I believe we will succeed. We will have our beautiful, prosperous, peaceful world. We already have it on a good portion of this earth. I'm going to go outside and enjoy some of it now.