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Apple will just say that it's a "new" sensor that is 1 in a gazillion more secure. They do stuff like that all the time. The rest of the industry is likely to move toward fingerprint scanners under the display.
Because the rest of the industry doesn't have usable face recognition...

And Apple has only once moved on to a more secure sensor for security...from TouchID to FaceID...today.
 
For a phone that is supposed to be the "path forward for the next decade", I think we can do better than thinking we can go back to the stone age with passcode fallback and the FaceID.

The real future should be we can use FaceID or TouchID as primary, and have either FaceID or TouchID be the fallback. Shouldn't even have to deal with passcode unless we really wanted to. That's what a real forward thinking device would have us do. Not one that forces us to go back to swiping up and other nonsense.
Touch ID and Face ID aren't a passcode themselves. They provide a go/no go response from the Secure Enclave to the OS which then passes credentials to the app or Apple Pay controller.
 
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