With the current iPhone cameras for sure battery life would be a disaster, so for something like this a low res, ultra-low power mode, or even separate sensor would be needed. As long as this data is only ever used for the pass through function, isn’t stored and is not available to apps (similar to how Vision Pro apps never get access to the camera feeds, nor data on where a user is looking, despite those feeds and that data being used by visual effects in the apps) I don’t see why there should be any privacy issues.It’s an interesting concept but having the cameras constantly active will destroy battery life, not to mention raise privacy concerns. All for a visual effect that doesn’t improve the functionality of the device in any real capacity.