In copyright law, original does not mean new. It means that a person originated the work. Here, this was done by a computer. Remember the monkey who took a selfie who couldn’t originate a work, and therefore there was no copyright work to be owned? This is a monkey on a typewriter.
Copyright law protects expression, and the labour required to produce that expression. Just like people who copy others’ work to gain from it, the “authors” have attempted to gain from doing no work and letting a computer give them all the world’s music. Imagine if they didn’t release their library into the public domain, and instead started to immediately sue over every new song that came out? It is fortunate that they cannot do either.
Copyright law protects expression, and the labour required to produce that expression. Just like people who copy others’ work to gain from it, the “authors” have attempted to gain from doing no work and letting a computer give them all the world’s music. Imagine if they didn’t release their library into the public domain, and instead started to immediately sue over every new song that came out? It is fortunate that they cannot do either.