Google's business is advertising. Right now they don't care whether your phone is "authentic" or secure, because it doesn't cost them money. As AI-enabled bot fraud rises, they will care. Fighting this requires identifying human beings, and that requires trusted devices to be associated with human beings. We're in the foothills still, but look forward and up at where adtech is going.
How is a trusted device associated with a human being? I'm pretty sure the walls of hundreds of bot phones are running trusted Android.