Strange case, some people were reporting the latest DSTWO firmware update didn't work on 3DS 3.0.0-6, others were reporting it did work. Others were reporting it worked at first, then just stopped working after a couple of days.
This fix is obviously for those people where the latest DSTWO firmware didn't work.
The only DSTWO's that were ever bricked were caused due to DS hardware malfunctioning and losing power before the DSTWO could complete the update process. I think those are permanently bricked, so no luck for users who had that happen to them.