The Cretaceous was a thing. The atmosphere had about as much CO2 as it could hold. There were lots of animals. We're headed back to it.
Will there be Eastern Brown Pecker Grouse habitat? No. Will there be coral reefs? Lol no. Will most of the pages of National Geographic be unrecognizable by the naturalists of the future? Yup.
But life will continue. All we're doing is robbing future generations of the myriad beautiful and delicate old growth ecologies that we were taught about in school. We can go snorkeling in them, or hiking in them. They'll just watch 1080p videos of them on their AR glasses.
We're headed back to the Cretaceous. We're going to take the biodiversity of the planet down two orders of magnitude. Maybe four.
That's all.
If we coders get our act together we'll get a decentralized anarchist bioremediation movement going which will rehome millions of acres of biome to Cretaceous-friendly locations, we'll limit the biodiversity loss to that 100x range. 10x if I'm feeling optimistic and smoking really good weed.
I think we can do it!