Is the media a bland, homogenized, corporate entity that crushes independent thought in favor of profits? If you ask many on the left then the answer would seem to be yes.
Is the media a haven for social liberals who are hostile to conservative religion and values? Yes again, if you ask nearly any conservative.
So who's right? Well, they are both quite wrong and a bit right.
The media IS overrun with self-described liberals who are independently hostile to conservative cultural and political values. It's true. Then again, the corporate media entities are obscenely interrelated and unquestioningly profit seeking agents. Those facts alone do not explain the full nature of the media's bias.
The simple truth is that the media is primarily biased towards statism. Why though?
Simply because journalists aren't the heroic truth seekers that they have portrayed themselves as since the 1950's (before that, journalists were often portrayed as fools) in films like Deadline U.S.A. and All The Presidents Men. The media is just like every other business in the world and most journalists are stupid, lazy, and don't want to do any more work than is absolutely necessary to please their boss so they can cash their paycheck.
Many, if not most news articles and reports are not written by so-called journalists but are simply reprinted nearly verbatim from press releases. The stock footage behind the talking heads is generally prepared in advance by some source or public relations firm and hand-fed to major news outlets. Journalists publish this prepackaged work rather than research their own material simply because it's easy.
If you are pursuing a story about the economy then talking to economists and businessmen would make a lot of sense. The same goes for ethical issues about abortion, legal theory about states rights, or science issues. The problem is that academics, specialists, and businessmen don't have press releases ready for publication nor handy-dandy stock footage ready for air. Governments, on the other hand, do.
Government manipulates the media by capitalizing on its primary weakness: it's need for immediate, new, easy stories ready for print. Government agencies provide a plethora of "sources" for lazy journalists and those sources will almost always trend towards the statist.
Governments employ hundreds of thousands of people (beyond attention seeking politicians) and those people are the real source of media bias. Their careers thrive, regardless of their political affiliation, on big government. The more government does, the more work they have. Statism is good for their careers and as a result, they favor it in their media relations.
A journalist reporting a story on the environment will likely use the EPA as a source; the pentagon or state department for a foreign affairs story; the treasury department or federal reserve when writing about the economy. Rarely will they consult an ecologist, historian, or businessman. They don't pursue the truth but rather the easiest story and that is almost always means a pro-government statist tainted story.