The mentioned tamper-evident-ness. E.g. the device can display at boot time a warning if any changes were made, or if keys were added to the trusted list. Addin

The mentioned tamper-evident-ness. E.g. the device can display at boot time a warning if any changes were made, or if keys were added to the trusted list. Adding extra keys can easily be locked behind a password that the owner can change. Note that this is not hypothetical - lots of unlockable Android phones will display a warning that they were rooted on boot.