I've been following this because I'm interested in virtual worlds. There are at least four virtual worlds that use some kind of NFT thing to register land ownership. Nobody does much in those worlds, and the graphics aren't all that good. It's all about trading land and speculating in some minor cryptocurrency.
The newest entrant - Zero Space.[1] The actual 3D world is promised for 2024. They already have five cryptocurrencies of their own, plus an NFT system. Their "3D world" is a simple un-shared Unreal Engine demo. They claim they will have a high-resolution metaverse, but show no indication that they have any idea how to build one.