I can’t remember having Obsidian Desktop create the very specific Obsidian iCloud Drive folder (as it doesn’t need it)… Mobile (iPhone/iPad), yes (as it’s required), but not Desktop 
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But then, that was quite some years ago 
and I could just be wrong 
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All I know, is that when I tried to sync a vault (for the 1st time) between my devices (Mac/iPhone/iPad) I used Obsidian Mobile first (at that time) and then only my Mac 
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