Because the media code set by the government should, in an overall sense, benefit the people of the nation. Clearly it's not the case, and the government deserves to be called out for it.
All I can find is that it was tabled by the Australian Competition and Consumer Commission at the request of the federal government. But if I was to take a wild guess, I'd say that Murdoch was somehow behind it.
You do know who conceived of this legislation in the first place though, don’t you?