There are many observations made in the book and one of them is that a supply chain and/or market can move itself quite efficiently without outside regulations and controls.
The book was written when the US was still a colony of England. It was written before we knew how to produce electricity. I don't think it can say a huge amount about the modern world.
I tend to view capitalism as a process rather than an end state. I don't see how it can have an equilibrium position. I am not educated in this either, so forgive my ignorance, but if the contention is that a system based on the pursual of self-interest and profit at the expense of others (because capitalism is a competition, isn't it?) contains within itself some invisible mechanism that pulls society towards economic stability and equilibrium... then it just sounds like wishful thinking. I mean, the 2008 crisis couldn't have arisen unless the excesses of capitalism had increased instability to such a point that everything was ready to collapse. Perhaps the answer is that I misunderstand the concept, but it perplexes me that some people still believe that an invisible hand exists, and my only conclusion when I compare this belief to the utter absence of evidence for its existence, is that it is simply a psychological prop used to support an idea that is outdated and incorrect.
This is one of those threads that opens up many avenues of discussion, and I may be veering off-topic.