Edit: Even if Apple were to require authentication before updating the software it doesn't matter because of the third immutable law of security:If a bad guy ha

Edit: Even if Apple were to require authentication before updating the software it doesn't matter because of the third immutable law of security:If a bad guy has unrestricted physical access to your computer, it's not your computer anymore. The FBI can still load FBIOS directly into RAM since they have physical access. But this is a much more cumbersome procedure since they need to pull parts off the board and probably need to spin a new PCB and they can't automate it the same way as if they were to do it purely through code.