I personally believe there may be more truth to that statement than many wish to believe, but not as a direct result of climate change itself. Rather, it's much more likely that the growing stupidity and political polarization surrounding climate change (and many other "hot-button" topics) will drive humanity to the ultimate stupidity of another World War, which these days can absolutely be a life-ending (on a planetary scale) path to go down, considering the types of "mass destruction" weapons the mad-men in power these days have access to.