Facebook Horizon is not the metaverse. VRland.io is the closest to the metaverse as any platform I've seen out there, it can be described as a web-based VRchat that not only works on headsets via WebXR, but on mobile phones and computers via WebGL. The metaverse needs to be a spatial, immersive layer that's architected off the back of our current 2.5D web. No 30% fees from walled gardens, and interoperability due to the platform-agnostic nature of the web.
Try out VRland here: https://vrland.io/