Final answer:
The journalist's argument concludes that the government's control over information should be lessened to maintain a free marketplace of ideas.
Step-by-step explanation:
The conclusion of the journalist's argument is that the control that governments have over information needs to be reduced. This is directly derived from the journalist's assertion that a free marketplace of ideas is essential for all ideas to receive fair consideration and that even those ideas that might be prejudiced or malicious can lead to positive outcomes. The journalist points out the contradiction in governments' roles where they are large disseminators of information through media while simultaneously being expected not to suppress free expression. This leads to the journalist's conclusion that the government's power over information should be curtailed to preserve the dynamics of a free and unbiased flow of ideas.