Passthrough with Apple VisionOS & Unity

Documentation from Apple implies that you cannot do pass-through / mixed reality if you are doing your own rendering. https://developer.apple.com/documentation/compositorservices/drawing_fully_immersive_content_using_metal

Is this something that also affects Unity, or does Unity have a way to work around this limitation (e.g. private API from Apple, or something I am missing so far)

This page seems to imply that it is possible: https://docs.unity3d.com/Packages/com.unity.polyspatial.visionos@0.0/manual/PolySpatialMRApps.html

Can someone help me clarify please?

Thank you!