Wow! Such negative predictions.
I imagine that we will have many difficult eras ahead of us as a species. I think that we will leave earth and populate other planets, and that the residents of each foreign world will evolve in different ways, and perhaps billions of years in the future, our descendants residing on planet x will not even resemble our descendants residing on planet q.
I hope that we do not destroy earth before this all happens, and that this beautiful, complex, amazing planet survives until our sun's life cycle ends.
Can you imagine how we might evolve after millions or billions of years residing on other worlds? Different gravity. Different chemicals interacting with our bodies. Survival traits among early generations based on resistance to some strange bacteria-ish thing, or resistance to particular effects of radiation, or something that we cannot even imagine in our wildest dreams. Our descendants' eyes will become accustomed to a different kind of light. Our eyes will change. Our bodies will stretch out, or become more compact. We will learn to bounce or roll to get from place to place. Our brains, I hope, will continue to evolve, and we will know the answers to questions that right now, would not occur to us to ask.
If there is any documentation of this era, and if there are historians who study it, they will be baffled by our silly fears and superstitions, and equally baffled by our lack of fear over our self-destructive behavior.
I think we will survive as a species. Perhaps we will branch out into various amazingly different species... as far from our current state as we are from the first amphibians who took a breath of air.