That's insane to write so many words for a theory so easily proved wrong. He shows that France was already transitioning from high to low fertility rate by 1800 despite artificial lighting being incredibly rare (90% of the population was rural).

The same source shows that Germany and England started their demographic transition end of the 19th century despite being more urbanised.

The effect should be bigger in northern countries than in the southern countries but Norway, Denmark and Sweden started also their transition at the end of the century, and today they have a greater fertility rate than Spain, Italy or Greece

Birth rates decline with female education, from long before leds were invented.

It's hard having kids but cultures like Japanese and Korean make it so hard on women - expected to care for both sets of aging parents and grandparents as well, bullied by the husband's mother and lumbered with childcare and cooking, I don't think we need to trouble this guy for his 'theories' to see why as soon as they have a choice, they nope out.

Something about correlation and causation comes to my mind. When you start an article listing all the known causes and they all relate to a high income (people in cities have more money, people in richer countries have more money, people with better education have more money, people with electricity have more money), why would you just dismiss this relation and claim that it's something else that seems to correlate nicely with high income as well (cities have more lights, richer countries have more lights, people with better education have more lights, people with electricity have more lights)? Surely a proof that high income is not the root cause is needed here.

Also, I don't really see the supposed collapse of birth rates after 2015, at least it doesn't seem half as drastic as those in the 70s (which can be explained by people having more money) or the ones caused by war.