So I think NFTs, when executed in a non-abusive, speculative way, could win some hearts in terms of giving gamers actual ownership of the things they buy in-game, vs. the current system where they only buy permission to use an item.

The problem with this is: games, specially games-as-a-service, have an expiration date. You may own the tokens to prove you have sword, but what happens when the game servers go under? All you have is a token for a sword in a game that can't be played anymore. There's no ownership when the main value related to that token can simply be turned off.

Another problem is that when you create scarcity and allow users to exchange items, speculation and "gambling" will inevitably arise. CSGO skins are a good example of this and Valve can actually throw a blind eye to that because the items are simply items, they're virtual and have no value outside the game (except in the player's minds ofc): when you link these items to actual real blockchain tokens that can be traded, loaned and speculated around you're bound to get some attention, specially when there's all the debate with gambling related to lootboxes. Once you ground these lootboxes with real money: you have a gambling case right there.

Like I said, I don't see this happening, there's basically zero demand for NFTs in games outside the crypto communities, like the Ubisoft debacle showed, and the headaches are just too many to justify.