@varx @aparrish @sprawlbug So in short - it changes how you interact with the hardware. Before hand your OS would need access to the camera/mic to implement random features, and malware / bad apps could just open those in the background however which way they could to gain unfettered access to stuff they shouldn't.
Now you can add things like wake word, photo auth, audio auth, etc by pushing biometric info to the secure enclave and getting auth results out, without granting access to hardware.