Comment 3 for bug 1931077

So to summarize:

-your drive failed
-you ssh'ed into the machine and started a service that required the drive
-systemd put the system into emergency target
-you switched to the backup partition and systemd exited the emergency target
-the emergency shell is now inactive, but of course its output text remains on the screen

If that's a correct summary, I'm not sure what you wanted systemd to do differently?