Its just a skybox with the cubemap of the room, no? The Quest 3 does a full room scan and can you get a 3d mesh of the room as well. They could provide a cubemap as well.
Meta doesn't want to pass any of the camera feed to an app for privacy reasons so they don't make it available but its a legal issue not a technical one. They can (and should) do this for the browser model viewer.
Apple enforces a single material model so they can inject the lighting data in a uniform way. Its a bit of a nuclear option to have a fixed shader pipeline. But I digress...
Meta doesn't want to pass any of the camera feed to an app for privacy reasons so they don't make it available but its a legal issue not a technical one. They can (and should) do this for the browser model viewer.
Apple enforces a single material model so they can inject the lighting data in a uniform way. Its a bit of a nuclear option to have a fixed shader pipeline. But I digress...
Anyway, its not as out of reach as you claim.