>>213036402so in this case it's not just about diversification but also complexity of the single sectors, right?
It's based on what you export really. If it's complex and diversified (eg. cars) you are complex, if it's simple and commoditised (eg. coal, oil) you are not complex.
>And what do you think it says about Japan specifically for instanceWell it's a good thing to have, but must be contextualised. Note that every country at the top is really poor in natural resources, so that's also why their index is higher. But yes in general its good, and often highly complex economies tend to have a more educated population, a more equal society, they tend to be more democratic etc.
Japan's problems do not really stem from its economic complexity, but much like Italy's, from its low labour productivity, enormous public debt, ageing and shrinking population, etc.