If there was a way to BACKUP one’s logbook manually, and/or start MSFS with a batch file that first backed up the Logbook, that might help a lot of players retain their data, while this “LogBook data loss” is occurring.
I have not looked specifically for this, but I remember seeing the logbook file somewhere, which was not directly Human Readable (Binary), but there is probably no reason why it cannot be backed up & restored when MSFS is not running ??