If we could just remind about Adam Smith and the invisible hand?

Well, yes and no and sorta:

In truth, this argument traded upon a long tradition in economics, stretching back to Adam Smith. In The Wealth of Nations the Scottish sage argued that when people act according to self-interest, they are led “as if by an invisible hand” towards the common good.

There are three Smith references - only three - to “invisible hand”. One is about the movement of the planets which is not really an economic matter, the second is in Theory of Moral Sentiments and is also not what is meant here. The third isn’t about the glories of free markets, the efficiency of capitalism or anything else. In fact, it’s about an inefficiency brought about by human nature. Even if - Smith quite clearly sets it up so that the “even if” is understood - investing in foreign parts is more profitable some will still invest at home just because they prefer to. That being the invisible hand that benefits that home economy through investment in it.

It all has much more to do with “Nudge” theories than it does anything else, a quirk of human behaviour that we observe. A quirk that actually works against that naked self-interest of the capitalists.

It seems incredible, as I look back, that in three years of studying economics in the early 1990s

A small recommendation for Mr. Syed. Try reading the source texts again and this time pay attention. Still true that most of the stuff about silver currencies can be skipped of course….