The judgement goes on and on about originality and similarity and labour and skill. Certainly, that demanded a careful and fine examination. But really, this is all nigh on irrelevant. The only thing that really counts is the commercial impact. This is because the sole substantive purpose of copyright is to create market conditions to support production. Yet the commercial question seems, on a quick reading, entirely absent.
Of course, the lawyers can only work with the law as it is; the problem is deeper. The law seems like it is trying to do the wrong thing. Restricting copying when it has no effect on original production is utterly counterproductive. If someone copies, in a case like this, we can presume it was because the material copied was good. And if they use it to sell a product, we can presume -- since they are actually making sales -- they are providing some useful service. Again, that is good. And if the copying has no detrimental effect on the original's commercial use, then we cannot have even a contrived sense of harm being done. So then one ought to ask: what on earth is the law doing preventing good and stopping no harm?