The answer is no. There have always been existential issues for humans. One that comes to mind right away is the Black Death in 14th century Europe. I don't see why climate change makes a difference now. Unfortunately, for them, it will be our grandkids that will have to figure out how to move forward.
I mean look at it this way... If no one had kids, then we would wipe out the human race, which itself is unethical. So if having kids was unethical, then it would also be ethical. A philosophical paradox. Having kids can never be considered unethical in a macro point of view.