That's the interesting subject of this case. But the fact is that 200 pages of a copyrighted work were copied, and there is an interesting legal question as to whether that copying does, indeed, constitute copyright infringement (i.e. whether it's protected and, if so, whether it's fair use). That Google intentionally did not try or want to achieve compatibility is another important detail that the court focused on, as well as the fact that they did all that for commercial purposes (here we're actually seeing that copyright has three stages: 1. determine whether the work is of a nature and form that is copyrighted. 2. determine what kinds of copying are protected. 3. determine whether protected copying was fair use.)
None of this, however, is relevant to discussions of works that are not copyrighted in the first place, as they do not even satisfy the most basic necessary conditions, like algorithms and protocols, of which REST "APIs" are instances. The case is about stages 2 and 3; they fail at stage 1. Partial, translated, complete, verbatim etc. copies of non-copyrighted works is outside the bounds of copyright law, and have nothing whatsoever to do with this case.
None of this, however, is relevant to discussions of works that are not copyrighted in the first place, as they do not even satisfy the most basic necessary conditions, like algorithms and protocols, of which REST "APIs" are instances. The case is about stages 2 and 3; they fail at stage 1. Partial, translated, complete, verbatim etc. copies of non-copyrighted works is outside the bounds of copyright law, and have nothing whatsoever to do with this case.