Any commodity producer that accepts the yuan instead of the US dollar must know that capital controls and price fixing are very important threats, and there is no real indication that the People's Bank of China is going to change any of those.

The reality is that the yuan has all the negative elements of fiat currencies—massive printing, lack of real support, central bank incentive to erode purchasing power—and none of the benefits of the dollar, the euro, and the pound—the free-floating pricing, legal and investor security, and an open financial system.

Saudi Arabia might use some yuan in its oil exports, but the reality is that no fiat currency with capital controls is a real alternative to other fiat currencies and that the advent of central bank digital currencies makes this difference more significant. Central bank digital currencies are surveillance disguised as money, and the risks of massive printing, erosion of purchasing power, and control of transactions are much larger than under traditional currencies.

Saudi Arabia could flee to gold or cryptocurrencies to escape the money-printing machine. But it will hardly replace a heavily printed but open and secure fiat currency, the US dollar, with a closed and less secure one.