The unsuspecting public believes they are objective. The media believe they are advocates for liberalism and the progressive Marxist agenda.
Journalism is interested in attracting the attention of the public, but interesting the public is quite a different thing than the public interest.The only way to even attempt to be objective is to begin with an analysis of one's own interest. Claiming to be objective, as journalism systematically does precisely to promote itself and its own interest is inimical to any effort at actual objectivity.
Belief in the objectivity of journalism is illogical.