Secondly, "a set of facts" *is* copyrightable, if there is selection or arrangement of those facts. OSM is a selected, organized, cross-linked set of facts expressed in a non-human language.
If you are going to claim that OSM is "*nothing more* than a set of facts", then you should be able to provide a simple and obvious explanation of what category of facts OSM covers. For instance, the white pages is "a listing of the name, address, and phone number of every person in a certain geographic area".
What is OSM? "A listing of all geographic facts about the world"? Certainly not. What is it? What is the *idea*, which you are saying can be merged with the *expression*.