Your explanations are textbook idealizations but don't hold in the real world (at least in the context of this discussion) and leave out some very important fac

Your explanations are textbook idealizations but don't hold in the real world (at least in the context of this discussion) and leave out some very important factors. For instance, while it may be positive sum strictly for trading partners, the positive value accrues to a smaller percentage of the population (i.e. the corporations and shareholders) and frequently even comes at the expense of the worker (or ex-worker). This is in large part why we are seeing the economic inequality that you referenced. It is a product of the "zero-sumness" of the game when viewed in total vs. just between trading partners/corporations.