In vanilla Civilization VI, Adam Smith is a valuable addition to your empire. The extra Economic policy slot will be useful for any type of victory. The Governor Title that he provides in the expansions is still useful, albeit easier to obtain through normal means than an additional policy slot.
Neither wealthy nor financially secure, Adam Smith nevertheless had a profound effect on world economics. Solely because he wrote the “bible of capitalism,” the first scholarly work to analyze the generation and distribution of wealth.
Although the date of his birth isn’t known, Adam Smith was baptized in June 1723 AD in Kirkcaldy, Scotland. His father was a judge advocate and comptroller of customs in Kirkcaldy (so perhaps money was in Adam’s blood if not his pocket), but died two months after the birth of his son. Adam attended the Burgh School in the town, where he learned Latin, mathematics, history, literature, and so forth. At the age of 14, he entered the University of Glasgow, studying “moral philosophy," and in 1740 went on to Oxford University.
Sponsored by the Philosophical Society of Edinburgh, Smith began offering a series of public lectures on economics and morality, as well as more prosaic talks on rhetoric and the like. Now a Doctor of Law, in 1766 Smith returned to Kirkcaldy and spent the next decade writing his magnum opus in relative obscurity … at least until it was published in 1776. It was an instant success, the first printing of 'An Inquiry into the Nature and Causes of the Wealth of Nations' sold out in just six months. In it, Smith concluded that a free-market economy was the most productive and beneficial of systems; such a system based on individual self-interest was a big hit with entrepreneurs everywhere.
Over the next few years, Adam Smith would hold a number of positions, ending with appointment as the rector of the University of Glasgow in 1787. He died just three years later at the age of 67.