But if you use dirty money to buy a good, it doesn't magically turn into clean money. A possible scenario could be where the buyer has clean money and wants to pay the seller for services by bidding way too much for a rare game. It doesn't make too much sense though because now your transaction is under scrutiny by the entire world?
Not when you have bazillions of ways to do that without being in plain sight. NFTs seem to better fit this need, and even then I don't get why people always assume it has to do with black money