In the article he talks about how demographic problems in Europe will slow economic growth. There will not be enough workers, but too many elderly. By 2040 Europe may be 1/3 elderly. He claims the graying of Europe will stifle innovation.
What he doesn't mention is that the problem is worse in China. Due to the one child policy demographics are skewed. Plus China isn't wealthy and doesn't have a pension or health care system for the elderly. Even the US, the least liberal developed country, still has a pension & health care system for the elderly.
One of the motivations for setting that up was realization that it would free children to pursue their own careers rather than be care givers and to support their parents. Think of all the people with good work ethics and advanced educations in math, science, economics, etc. who would have to stay home to take care of their parents if not for medicare and social security.
The worker to retiree ratio in China in 2040 will be 2:1. They will have 400 million elderly by then, making up about 25% of the nation.
So every demographic time bomb he predicts will bring down Europe is going to happen in China too. Plus China doesn't have the resources or infrastructure Europe does to deal with it. China doesn't have a developed health and pension system to care for the elderly like the US & EU do. Which means it will fall to their kids to not only take care of themselves and their children, but their parents too.
So what if Europeans have a little fun now and then? Well, fun has consequences. Declining fertility pushes up the age of the citizenry and shrinks the percentage of people in the workforce, and so impedes growth. Demographic changes also shape the hiring and promotion structures of individual companies, and not necessarily for the better; if the elderly cling to the best jobs well past retirement age, younger workers may have to wait an extra decade, perhaps longer, to get their turn. And because younger workers are a major source of new ideas, slowing down the ascendancy of the next generation may retard the pace of technological change. (If fertility rates remain as low as they have been, Italy's population will fall by half in 50 years. Naturally, politicians are doing everything they can. They are joining with the Holy See and telling young women: Please procreate.)
He makes no reference to how having 400 million elderly in China in 2040 will affect their society (25% of their population). But he claims the same problem in Europe will destroy their civilization's economy. He also makes no mention to how China's problems will be even worse since they are a developing nation. In the EU there are pension and health care systems, so people feel more comfortable retiring and allowing a new generation to take over. That isn't the case in China. People face more economic insecurity in retirement than in the EU and as a result have less incentive to retire.
Also, I didn't see the author talk about the role of natural resource shortages. We are hitting a point where many raw materials are seeing demand outstrip supply. I don't know what effect that will have on growth, but I don't know if he addressed it properly. He didn't bring it up.
I don't know tons about Fogel, but is he a neoliberal Friedman type? I saw he taught at Chicago. Plus his solution to the European crisis is basically to tell Europeans to become more workaholic and have more kids (which sound like right wing solutions). He also seems to have a problem with feminism, birth control and sex for recreation.
All in all, I'm not convinced. His economic GDP numbers seem way off. He seems like a right winger (he comes across as a neoliberal social conservative, which makes me question his validity since those kinds of ideas almost collapsed the global economy recently). He doesn't account for demographic problems in China, he just ignores them while claiming the same problems will destroy Europe, even though Europe is better equipped to handle them.