Inept analogies abound - an entire ecosystem of them
To select just one - "But far more dramatic changes in the climate have been experienced within the past 20,000 years, Lilley contends, with humans able to draw on far more primitive technological resources, and yet survive."
Back then we had nomadic hunter gatherers. When it got cold, which it did gradually, people moved to warmer areas. When the local animals died or were killed, the people moved to the next valley or died. Many must have died - those who did not decide to move south.
With a lightly populated planet and far more animals (food) than people, it was an entirely different problem.
Today, without imported food, most of the northern parts of the planet would soon die of starvation. Any argument based on conditions 20,000 years ago is simply too stupid to be considered. Any writer who repeats it meets the same assessment.
And, yes, when I read the title on the splash page, I did guess that it was by Orlowski.