So what you're referring to is that he had some unit started within some user's scope and then killed the scope which promptly stopped his unit. This behavior w

So what you're referring to is that he had some unit started within some user's scope and then killed the scope which promptly stopped his unit. This behavior was actually not the default on most distros until not too terribly long ago. Basically, the way this used to work was that on logout, all of the user's processes would get signaled that they need to close but it was up to the application to handle how to respond to that signal. Sometimes daemons would misbehave and there's nothing to differentiate "this app is supposed to end but hasn't" and "this app is choosing to ignore the signal because it needs to stay running". With systemd, there is an option to reap these processes so that when you log out, you never have to worry about some misbehaving process hanging around and causing problems when you log back in. The way to fix this without disabling the feature is by explicitly putting the process in it's own scope. That doesn't take special permissions to do, it's just that it needs to be done explicitly instead of just ignoring SIGHUP.