An important question that should be faced by libertarians, anarchists, and anyone else interested in freedom of speech is: where does voluntary persuasion end, and coercive deception begin? The question is far from simple, and the answer is far from obvious.
In theory, privately owned media are under no obligation to present information that is accurate, balanced and complete. The recent presidential election demonstrated that. In an early debate on libertarianism many years ago a person who identified himself as a libertarian claimed that in purely ethical terms, if someone asks him for the time, he's under no obligation to tell anybody the correct time. I don't think his claim was intended to defend anti-social behavior, but merely to illustrate that in a truly free society you have no obligations to anyone that you haven't agreed to in advance.
In contrast, a collectivist would assert that by being a member of a community, you are indeed obligated to avoid misinforming fellow members of the community. That is also a good, practical strategy, since failing to be a reliable source of information damages your credibility even when you are telling the God's honest truth and your life may depend on it.
Some people naturally become cheaters: they encourage others to always tell the truth, and they are truthful themselves most of the time to maintain their credibility, but once in a while when it's to their selfish advantage to lie (and they think they can get away with it), they will attempt to deceptively coerce others through information that is inaccurate, imbalanced, or incomplete.
The problem isn't merely the quality or quantity of information, but also the skills needed to evaluate information. One way to combat that problem is to teach children critical thinking skills, including elementary logic: what's the difference between inductive and deductive reasoning, and when is an inference valid or weak? If kids are taught critical thinking skills, they will also learn media literacy.
Traditionally, those in power have tried their best to keep common people as ignorant as possible, so that we are easier to manipulate and control. Some parents, in turn, do the same thing to their children. I think an ideal libertarian society must confront the need for comprehensive early education (not necessarily in schools), otherwise we will merely create fertile ground for the very interpersonal coercion that freedom-loving people claim to oppose.