I doubt that child pornography is even the true reason behind these laws. If anything, that problem is at its lowest now in the entire human history, at least in Europe. And the form of "violence" these laws are trying to limit have to do with bytes going over the Internet, not directly with children being kidnapped or sold into prostitution. I'm not saying that these laws couldn't be used as tools to go after actual human trafficking networks, but their scope and the damage they do is vastly disproportional to that objective.
More likely, the true goal is to introduce novel forms of policing, and widen them bit by bit until we do become true surveillance states, where every word any citizen ever said is stored in some government archive.