^^^This. You are NOT allowed to give up hope or let the efforts of thousands and millions of your fellow human beings and ancestors go unrecognised like this! Get your ass up and stop moaning, and go plant a tree! If you live in the northeast, give money to the people reviving the American Chestnut. If you live in any part of the east, plant a fucking sycamore. These are the keystone trees out here, and if you can't plant one, then go LOOK for them! The American Chestnut Foundation needs citizen scientists to go out and look for old trees so they can collect pollen and help keep the revival genetically diverse and that's something you CAN do, right now.
If you live in the UK, look up Reforesting Scotland, an organization for doing exactly that. Or the Great Northumberland Forest if you're in England, or The Native Woodland Trust in Eire. India has Greenvein, and there are many others that I found just looking up the Reforestation category on wikipedia.
HOWEVER, as a desert-dweller I want to make clear that forests are not the only biome that needs protection and restoration! If you live somewhere that isn't supposed to be a forest; that is chaparral, desert, prairie, or wetland, remember that those biomes are equally important and healthy too--and beautiful! And don't forget aquatic biomes too, like kelp forest, sea grass prairie, rivers, and lakes! (Corals are very charismatic but they are just like forests in that they're often myopically considered the only worthy biome.)
If you live in the gulf coast states of the US or other swampy areas, then champion your wetlands! Successful campaigns have replanted mangroves, which offer important protection against hurricanes and coastal erosion--this is badly needed in Louisiana and Florida for example.
If you live in Southern California, Arizona, and New Mexico, you live in chaparral country and desert country, and those are delicate and ancient biomes that have been devastated too and need help, particularly because so many people look at them and say, 'what a worthless waste with no life' and that is not true my friends! Deep roots are what old growth in deserts and prairies look like, and to that end we need to change how we think about farming and let deserts BE deserts, particularly since the deserts in the southwestern US are so badly treated by local industries, and so unique on earth!
I am lucky enough to come from roots that paid attention to the helpers and the revivals, the (successful!) effort to rescue California Condors was a success story that was local that I got to see happen in real time. You cannot sit there and succumb to apathy and giving up, I know you're tired and fed up but the only thing different now is that the information isn't buried, not that things are somehow worse. They aren't worse, in fact they are getting better because so many people KNOW now and are out there WORKING ON IT. You have to do that too! There's no 'or' you just have to!
You are not allowed to give up on our home!