It reads other files too, of course. Delete your machine-id and machine-info files, and the machine ID and machine info will also not be there for hostnamed to read, for example.
It actually names the latter openly on the hostnamed manual page.
hostnamectl gets its information across the #DesktopBus from hostnamed. And hostnamed in turn gets its information from reading the os-release file(s).
So when that someone has deleted your /etc/os-release (and /usr/lib/os-release and /run/os-release), you'll find that hostnamectl will not be able to give you the information. Because the information isn't there any more.
@kde a less experienced Linux user has just pointed out to me that there is no GUI in KDE for setting a system hostname? Or if there is we can't find it.
I've always just used hostnamectl, which is fine. But seems like an oversight!
#kde #plasma #hostname #hostnamectl #sysadmin #linux #areweblind
Am I missing something or should hostnamectl not have a --user mode similar to systemctl? (It doesn’t currently.)
JdeBP
GNU/Matt 
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