My oldest is quite intelligent. We've had "I bet she was breast fed" more times than I can count. The reply is "no, it's a combination of genetics and nurture"...
However, at the population level, which is what the healthcare system is dealing with, that's a huge deal. Imagine if the average IQ of the entire population were shifted up by several points.
I guess it depends on the starting point. I imagine that shifting the average from 85->90 would have a much bigger effect than shifting from 105->110. Most studies seem to show a pretty sharp diminishing returns when correlating IQ points to just about any measure of 'success'.
this is exactly what China has done during recent decades through the one child policy. And i'd say it starts to show.
Not sure the UK has a "smugness and superiority complex" problem. It sure has a "let's not allow anybody be different/at a higher level" problem though. Everybody is labelled "smug", "pretentious git" etc.
I mean, complaining about people breast-feeding being smug?
Let me summarise at a more abstract level; people are eager to differentiate from others because to be honest we're pretty boring and uninterestif, myself included. They do this by clinging onto all sorts of irrational non-scientific beliefs. Some of these become almost ritualistic'(squirting breast milk on a child's head rather than using dentinox to cure cradle cap). Then these beliefs turn into packs and factions primarily for maintaining supposed differentials and rituals. Other people don't care (like myself) but are somewhat vexed at the suggestion our time needs to be wasted on such things at every available opportunity. This is a bad human trait that manifests itself in many ways.
The nurture is where the causality chain starts.