Keyboard shortcuts in Obsidian (on a Mac) = cmd+P brings up the Palette, and then type "Move" and you'll see an option for "File explorer: Move file to another folder." Use your arrow keys to move down and select that option, press Enter, and now type in the name of the folder you're moving the file to. After doing this a few times, it becomes second nature and very quick! (At least, it did for me.)