I just now tried to start empires and I got a warning. "Steam was unable to sync your files for empires with steam cloud."
Controls & video settings probably sync. But those don't change often, it probably doesn't matter if they don't sync often.
Everything Steam went down completely and is slightly recovering now ofc the stats display doesn't include the downtime of forums, masterservers, website, cloudmasterservers, friendsnetwork, VAC2 etc.