The trouble with that is it's a central server which means an IT department to fuss with it.
Better would be something like Excel but that works P2P like SyncThing, or even directly using SyncThing itself.
I don't think it would actually be too hard as long as you didn't need truly realtime collaboration if you used file sync as your backend, and gave up on the 2D sheet model in favor of a table/records model that lends itself to conflict free operations instead of edits to specific numbered cells.
Better would be something like Excel but that works P2P like SyncThing, or even directly using SyncThing itself.
I don't think it would actually be too hard as long as you didn't need truly realtime collaboration if you used file sync as your backend, and gave up on the 2D sheet model in favor of a table/records model that lends itself to conflict free operations instead of edits to specific numbered cells.