Its also US only. Other countries will differ. This means you can only rely on this ruling at all for something you are distributing only in the US. Might be OK for art, definitely not for most software. Very definitely not OK for a software library.
For example UK law specifically says "In the case of a literary, dramatic, musical or artistic work which is computer-generated, the author shall be taken to be the person by whom the arrangements necessary for the creation of the work are undertaken."