Adam Smith's The Wealth of Nations was published in 1776. I suppose you could say that was "post-fact" as it drew on what was happening at the beginning of the Industrial Revolution and the English and Scottish agricultural revolutions among other things, but "invented" would seem a bit of a stretch.
> The law that "in a free market, the best product wins" has been beaten by profit-driven companies with billions at their disposal.
Of course, given that law then the other possibility you appear to have dismissed is that the market is not free.