* Able to be used on any carrier (i.e. no SIM lock)
* Able to be rooted/jailbroken (i.e. no bootloader root of trust lock)
* Able to be accessed (i.e. no screen lock)
This article is talking about the first one. There isn't much confusion possible in the title, especially with the dissenting carrier names highlighted.
Is that really something that gets confused often or any more often than any other disambiguation in the English language?
fastboot flashing unlock_critical
Also I wasn't as clear as I intended to be with sense 3 above - it might also mean temporarily screen-unlocked, as in "can you please unlock your phone so I can enter my number?".
This doesn’t work, though it seems to be a common misconception among engineers. Put simply, people will nickname neologisms. Creating a new term or pulling one from obscurity virtually begs for someone else to come up with a name people will actually use for you.
It is still shipped locked. Unlocking wipes the device.
It also doesn't work if your device is carrier locked.
Bootloader unlocked generally means that the vendor permits the execution of arbitrary operating system code, ie there is no jail to break out of.
In fact If I saw jailbroken in a listing I'd assume it's because the device cannot have its bootloader unlocked.