If the purpose of the Dark Web was just the sharing of information for free – information that perhaps is illegal in the real world – then it would probably do okay. I’m sure there are existing hidden networks that operate purely to share illegal images. Everyone is on the same side, and they want to help each other out.
But once you create a lawless community, there will immediately be some that wish to profit from it, or . A fine example is Second Life, which started out as a multi-player MineCraft and ended up being full of porn shops and anarchists bent on destruction.
So it was that Silk Road ended up being policed, even so far as people being threatened with physical harm if they did wrong. The problem, of course, is that it is hard to trust a crook:
Game theory suggests that without the possibility of retaliation, no buyers will enter into business in the first place, since they have every expectation that they will be cheated. There will, in short, be no market. Sellers will have no-one to sell to, and everyone will be worse off.
…This creates a market niche for intermediaries, who can become entrepreneurs of trust, supporting relationships between buyers and sellers who otherwise would not trust each other. Again, the Sicilian Mafia provides a precedent. Gambetta finds that they began as brokers of trust between buyers and sellers in a rural society without effective laws. The Mafia made money by guaranteeing transactions, threatening cheaters, and sometimes cultivating a general atmosphere of paranoia in order to ensure demand for their services. In other words, it built an informal order of its own, inimical to conventional laws, that gradually began to supplant the traditional state.
The above is from a great article at Aeon on the same topic. Libertarianism is fine ideal, as long as you understand that it is different from anarchy. There has to be a basic framework of control from authorities, so that freedom (and illegal activities) can flourish.
There will be a Dark Web one day, where you can trust the bad guys. It will be just like the Dark Web of today, except there will be an admission fee or a tax involved, and for that you get protection. The degrees of oversight required will mean those in charge will be vulnerable to being caught by real world authorities. So I don’t expect any too last more than a year or two.
Ultimately I expect that black market trade will primarily exist in the real world, not virtual. People will use the web for encrypted contact, and even payment and delivery, but there will be real world connections, so that retaliation is possible if need be.