What you seem to not be getting is that the damage to the environment is HERE. Hundreds of thousands of all kinds of species are DEAD and NOT COMING BACK. Water sources are DEPLETED and TOXIC, NOW. Etc. Plastic is on Everest and the Mariana Trench.

That's not Chicken Little, that's the denouement of The Boy Who Cried Wolf. Except in this case, the boy had decades of charts and photos and graphs showing that a whole pack of wolves were on their way.