Without independent media to provide different aspects and points of view, a government will generally cease to be a democracy(by the people, and for the people), and instead becomes some form of dictatorship. Whether it's one individual, or a ruling party controlling the media that is consumed by the public.
The media plays a crucial role in the function of government and in the running of society. If having a real and healthy democracy is important, then having an independent media is of the utmost importance. The media is what holds government officials and powerful individuals or corporations accountable. Democracy only works if people are informed and aware, and it is the media's job to make it that way.
Independent media is one of the important element that make a democracy what it is. Without an independent media, the citizens will not be able to gain the accurate information to make the right decision that may influence public policy. Without the independent media, the information would tend to be biased and may favor the party that held the power at the moment. The independent media act as a watch dog, therefore the party that held the power cold not be overpower.
A true democracy, where everybody has a voice in government, requires that the people be well informed and the government be held accountable. Independent media can help on both of those fronts. If the media is privately collectivized, it can be controlled by a small group of people, which takes power away from the people.
If you look at former Iraq and current China, you will see that government controlled media rips the rights from the people. They deny things that have happened that portray them in a bad light and control propaganda to a point that the citizens believe things which are false. In the US, independent media is still somewhat biased, but even then, people are still able to make their own decisions based on the massive variety of news sources they can use.