It is not imaging your face like a normal camera would. It is using an infrared camera to pick out the location of two dots (the relative position and distance of the two dots in the camera”s field of view). That information stream could be compressed to a few bytes per second without losing tracking fidelity. That does not seem very invasive. Even if a high resolution pixel stream were to be sent from the camera to an untrustworthy, persistence layer, it would be infrared, which doesn’t seem very privacy-invasive.