This is basically true, yes. the French keep an overlord status over the currencies of these countries through the CFA, and this is one of the major sources of French wealth. It used to be pegged to the French Franc and, after the end of the century, then to the Euro, strictly, but overvalued. That means, like other Euro countries, these countries have no monetary sovereignty and lack policy options to align budgetary and monetary policies. (The same thing sunk Greece.) The fact that it was overvalued made their resources horrendously expensive and ensured that they would only flow to France, which could print their money to buy it, ensuring raw material flow to France. At the same time, these countries are forced to hold at least 50% of their foreign reserves in Franc (and now Euro), strengthening the status of that currency on the world market and, of course, gains them those reserves.