That is mere pedantry however. Clearly the main point was that the effects will be undesirable because they will come at the cost of a lot of human life. Whether humanity as a species will survive is, arguably, of lesser importance.
The worst-case scenario is a collapse of civilization, which - with or without wars - means mass starvation (if you live in a large city, you'll die in the first week). Your grandchildren - or more likely, someone else's grandchildren - will be living in Mad Max hellscape, desperately trying to stave off reverting to pre-industrial levels of life and technology.
(And with all the easily accessible energy sources already mined out and gone, I suspect the next industrial revolution won't be possible for many, many millennia.)