The scans were made after the people filled in consent form. They included color, depth, and infrared data, as well as related information, such as how a person took a phone off a table. The Soli radar in the pixel needs the motion data to indicate when the face unlock should be activated. Google also confirmed the gathering of location information, but said the data was not needed and it would be deleted. The rest of the data will be deleted after 1
As already mentioned, Face Unlock uploads no data to the Pixel 4 on Google's server – it stores them on the Titan M security chip. Apple has also asked for facial scans when developing the TrueDepth camera and Face ID, although scans have been collected through studies and supplemented as needed to provide a wider range of samples.
Google played fast and easy with face recognition data. Similar to Apple, the goal here is to create a reliable face unlocking system that will last in real life, with facial hair, eyeglasses, make-up, and the basic aging process associated with facial recognition systems having devastating consequences. If you're more concerned with what's on your pixel than engaging in it, Google has accomplished its mission.