"Sync Playback to Display" is something that many PAL Users need and Kodi Developers don't want to fix it
There is a simple explanation for that. Currently there is no main Android developer in Team Kodi.
Why not archive 9.0.1 together with all Libreelec Addons for people who need "Sync Playback to Display"?
What do "all addons" have to do with 'Sync Playback'? Sorry, but packing 'all addons' with a release is total horse manure, imo.
Older LibreELEC releases should be available via archive.libreelec.tv .
And of course, you can always create backups of your own working setup yourself....