I wouldn't hold him the responsibility unless he uploads the files himself. I mean how could the uploader get away while the owner gets issues ?
It's pretty much like everything else in the world. If we take the Internet, for example , It could be used for both good and bad (for both selling drugs and for helping billions of users every day).
Kim Dotcom couldn't be responsible under any circumstances. He was doing what pretty much every computer-savvy person was doing: proving that the right to copy is actually now held by everyone equally.
It's simple: before 20th Century, there were no commercial recording industries, because there was no commercial recording technology. Before that, "stealing" music or stories didn't exist as a concept. Because the ability to control who heard the work was impossible, the idea that the music or stories belonged to anyone was meaningless. The original author was either known or unknown, and that was as much recognition as was realistic.
Fast-forward through the 20th Century, and we witness the rise and fall of the recordings replicators. And what killed them off was good old supply and demand: book/magazine printers, vinyl/CD pressing equipment and VHS/DVD presses
all were made more or less redundant by simple PC's on the internet. Where the supply was limited and controlled by the replication technology, the flood gates of perfect digital copies, available in a few minutes, had suddenly opened.
The old culture is almost dead: there are few practical reasons for using the old media, (I'd argue that physical books are the only truly useful old tech remaining) and so in slightly less than 100 years, a multi-billion dollar industry was born, and promptly died. And it's a very good thing: the 20th century celebrity culture that that colossal quantity of cash fueled is nasty, destructive and pointless (apart from the profits). The industrial scale oligopoly, the world-wide adulation and embarrassment of riches turned otherwise ordinary people into self-obsessed navel-gazers, and spawned an army of foolish mimicry. And people like Kim Dotcom and Bram Cohen drove a wooden stake through their collective hearts. Good.