[chrisco255]

Simple, there exists an open marketplace and game theory suggests that some game developer will figure out that aligning the player's interests with their own will result in a profitable niche for themselves.

You may not necessarily be able to use FFXIV health potion in WoW, but could you imagine that an up and coming 3rd party dev gave you a discount because you had a FFXIV NFT? Could you conceive of a group of indie publishers banning together to create a collaborative ecosystem of NFTs that all their games share and recognize? Could you imagine achievements in certain games unlocking secret levels in others?