My comment is not to do with TPB. My comment has to do with mixing legal principles (or more specifcally, areas of law) that are very different and do not mix well.
I disagree that "the same legal principle" applies, but then I'm not sure we have the same principles in mind. It sounds like you are thinking about the concept of conspiracy in general, or contributory infringement. But that's not what I was referring to.
In my mind, there is a clear delineation between what is criminal offence and involves bodily harm ("illegal") and what is simply an alleged violation of intellectual property or contractual rights (e.g. "alleged copyright infringment").
When someone jumps from one to the other, as the commenter did, it is very strange. Because to me they are two very different areas of law with their own distinct philosophical origins. That's why they are almost always separated into a criminal code and a civil code.
There are plenty of examples of conspiracy to commit civil offences. Ignoring them and using an example from criminal law, and in particular homicide, one of the most heinous of all crimes, seems unnecesary. It raises the suspicion that either the commenter is using this example merely for shock value or that his knowledge of the law is very narrow and not well-informed.