[BRLTTY] BRLTTY does not work in emergency shell

[Rob Hudson]

BRLTTY 6.3 on arch linux.
The other day there was a problem with some of my fs mounts, and I was kicked into emergency shell. I am uncertain of when this change took place, but BRLTTY no longer works there, although it did last year. I have made no changes to the BRLTTY default arch package. I could not even start it manually by typing
brltty
at (what I assumed) was the command prompt. And of course, I could not ssh in due to there being no network in emergency shell mode.
What changed in BRLTTY to cause it to stop working in emergency shell?