Without reading the article nor being an expert in intelligence (but hey, I'm a certified HN commenter), probably the reduced stimulation (reduced interaction w

Without reading the article nor being an expert in intelligence (but hey, I'm a certified HN commenter), probably the reduced stimulation (reduced interaction with friends and the wider world outside the home) is what was detrimental to intelligence development. To use an extreme comparison, children who were locked up in basements also come out being less mentally capable than their peers.