The reason Ubisoft is deploying this as an NFT instead of using the centralized market model that Valve uses is so they won’t be subject to the same regulation

The reason Ubisoft is deploying this as an NFT instead of using the centralized market model that Valve uses is so they won’t be subject to the same regulation that Valve has to deal with (reporting proceeds from sales to tax authorities). If the secondary market is on the blockchain and the money doesn’t pass through Ubisoft’s hands they can avoid dealing with this while still having “you can sell your items to other people” as a feature.