Because they protect against different actors. A stolen phone? The thief likely just wants to strip your phone down to parts and sell the parts if there is a pa

Because they protect against different actors. A stolen phone? The thief likely just wants to strip your phone down to parts and sell the parts if there is a passcode. If there isn't anything, perhaps the thief would wipe it and sell it whole as a second hand device. Only law enforcement cares about the difference between the AFU state and BFU state.