I believe that will actually disable the syncing of that data entirely, which probably isn't what you want because some apps rely on that sync. But nixme's com

I believe that will actually disable the syncing of that data entirely, which probably isn't what you want because some apps rely on that sync. But nixme's command-line tip above works to specifically fix the annoyance of having save dialogs always start with iCloud, while still allowing you to have it sync all that data.