You could describe inventions as "facts" too, are you saying that inventions shouldn't be patentable as well?
Maybe the fundamental properties of the universe aren't copyrightable/trademarkable/patentable, but what you CHOOSE to do with those - what API you design or what widget you build out of it certainly is.
Patents and copyrights are two very different things, though. I don't know if APIs are patentable, but that's a very different question. Has anybody ever successfully patented an API?
Maybe the fundamental properties of the universe aren't copyrightable/trademarkable/patentable, but what you CHOOSE to do with those - what API you design or what widget you build out of it certainly is.