First Amendment tradition stresses the 'widest possible dissemination of info from diverse & antagonistic sources' in an effort to promote goals such as informed decisions-making, cultural pluralism; citizen welfare, and a well-functioning democracy.
It is the mechanism by which First Amendment freedoms are translated into effective democracy.
First Amendment freedoms, in which citizens are free to choose from a wide range of ideas (content diversity), delivered from a wide range of sources (source diversity). The citizens then partake of this diversity (exposure diversity) to increase their knowledge, encounter opposing viewpoints, and become well-informed decision makers who are better capable of fulfilling their democratic responsibilities in a self-governing society.