Pixel is on generation 7. Only two supported face unlock: 4 and 7. 6 was rumored to have it, but it was never delivered. 6 and 7 are equivalent hardware-wise

Pixel is on generation 7. Only two supported face unlock: 4 and 7. 6 was rumored to have it, but it was never delivered. 6 and 7 are equivalent hardware-wise for face unlock: neither has the sensors to do it in a highly secure manner. 7’s face unlock therefore doesn’t give you access to the most sensitive stuff, like bank accounts, requiring supplemental, secure authentication, such as fingerprint.