This applies to every single form of game-based NFT. What incentive does a Game Developer have in implementing their items on the blockchain? So I can trade my WoW Health Potions for FFXIV Health Potions? In a kind world, when I'm tired of WoW I could safely transfer my wealth from WoW to FFXIV, but does Blizzard want that? Better to ensure lock-in. Further there will never be the case where a game like WoW would recognize an item from FFXIV as canonical and equal value. I wouldn't be able to buy a FFXIV health potion and use it in WoW.
The only games that will implement NFT items will do it as a gimmick. TCG, or normal game, or anything.
I have yet to see an actual compelling use case that solves a problem that game developers have. Remember, solving a problem a player has doesn't mean the incentives for game developers are aligned.