No one was even talking about the "metaverse" until Facebook mentioned it. After Facebook mentioned it, no one was talking about anything
other than what Facebook (or Meta) would do with it. Anyone looking to provide services or create content for the Metaverse is focusing on Facebook. All of the discussion on Hacker News about the metaverse is relative to Facebook.
There is no arms race here. There won't be many "decentralized" versions "using blockchain technologies." Maybe there will be one, and as with all other decentralized alternatives to social media, most people won't care about it. Everyone else will be using Facebook's version because everyone is already using Facebook and they already own the cultural mindshare. No one cares about NVIDIA's Omniverse.
Maybe Apple or Microsoft or Google also offer versions, but all of them will be centralized.
Sorry, you've already lost. And Web3 is just a scam.