That's a funny spelling of "Roblox".
I'd argue that scifi examples (like Ready Player One) show that it can be proprietary.
I'm not saying it's good to be controlled by one org. Just that the number of orgs controlling the infra has nothing to do with being the metaverse or not.
Facebook itself would be a better example to your point as it's the largest social network.
I've been seeing a lot of ads lately for an iOS game (an awful looking game, but that's beside the point) whose major claim to fame in their ads is that you can earn Roblox's Robux by playing. They probably aren't using any sort of federated Roblox "metaverse ecommerce platform" today, they are probably just laundering Robux gift certificates. (I'm not entirely sure, it's not a game I have reason to download as awful and creepy as it appears.)
So there are at least some game spaces they don't own. (Whether or not you agree those are worthwhile game spaces.)