Second Life was awesome! This Metaverse trend is pushing that concept much, much further and it's giving ownership and utility to the makers.
>you can buy a digital artwork at a Christie's auction and display it in Decentraland and have it be verifiably authentic
I can't imagine anyone would give a shit about someone's virtual art being "authentic" for whatever meaning of authentic NFTs pretend to claim. This is basically receipt porn at this point. Truly we're talking about bragging about wealth, one of the shittiest traits a person can have.
From a competitive standpoint, why would I want Activision's digital locks (you can only import NFT'd content) instead of something like Second Life which is more open?
If Activision really wanted purchases to carry over, they could've made it happen. No NFT needed. An open standard does not imply NFT, and vice versa. The 360 era was probably the peak of the 'gaming interoperability' trend, and it went almost nowhere. Your Xbox gamer picture would show up in some games. Everyone knew it was authentic because MS uses cryptography and doesn't let you sideload third party images. No NFT needed.
Same reason my company doesn't like me displaying awards from my last company. The obstacle is entirely social rather than technical.
Also for your other points - the games in this space are universally unfun to play with hardly anyone actually playing them; I can pay normal money to commission artwork; and I can use a zillion platforms that already exist to raise money.