Turn off camera in RealityView for iOS?

I am using RealityView for an iOS program.

Is it possible to turn off the camera passthrough, so only my virtual content is showing? I am looking to create VR experience.

I have a work around where I turn off occlusion and then create a sphere around me (e.g., with a black texture), but in the pre-RealityView days, I think I used something like this:

arView.environment.background = .color(.black)

Is there something similar in RealityView for iOS?

Here are some snippets of my current work around inside RealityView.

First create the sphere to surround the user:

// Create sphere
let blackMaterial = UnlitMaterial(color: .black)
let sphereMesh = MeshResource.generateSphere(radius: 100)
let sphereModelComponent = ModelComponent(mesh: sphereMesh, materials: [blackMaterial])
let sphereEntity = Entity()
sphereEntity.components.set(sphereModelComponent)
sphereEntity.scale *= .init(x: -1, y: 1, z: 1)
content.add(sphereEntity)

Then turn off occlusion:

// Turn off occlusion
let configuration = SpatialTrackingSession.Configuration(
    tracking: [],
    sceneUnderstanding: [],
    camera: .back)
let session = SpatialTrackingSession()
await session.run(configuration)