Actually, while the majority of big papers transitioned to "objective" journalism after the Civil War, a large number of "pennies" and other papers, well before the "Yellow Journalists," maintained a steady dose of sensationalism and crime.
Of course you're right about that; memory fails me from time to time. Just out of curiousity, would you say the print war between Pulitzer and Hearst broke the objectivity "agreement" amongst the major players; maybe breaking the dam? Possibly laying the groundwork for our current crop of propagandists?