Meade's bad press stemmed from the Cropsey affair. Edward Cropsey was a reporter for the Philadelphia
Inquirer. He wrote a story generally complimentary to Meade, but the final paragraph said, "History will record, but newspapers cannot that on one eventful night during the present campaign Grant's presence saved the army, and the nation too; not that General Meade was on the point of committing a blunder unwittingly, but his devotion to his country made him loth [sic] to risk her last army on what he deemed a chance. Grant assumed the responsibility, and we are still on to Richmond." Cropsey was referring to a rumor that after the Battle of the Wilderness, Meade wanted to retreat. The rumor wasn't true, but Cropsey published it without verifying it. Meade went ballistic. He published
general orders that first of all misspelled Cropsey's name as "Crapsey," then went on to banish Cropsey from the Army of the Potomac. That was bad enough, but Meade went further and ordered that Cropsey be paraded through the camp wearing a sign reading, "Libeler of the Press."
It was humiliating for Cropsey, but it was a Pyrrhic victory for Meade, because from then on the press correspondents agreed that Meade's name would never again appear in a story unless it was connected to bad news for the army. They never again referred to the Army of the Potomac as "Meade's Army." From then on it was always "Grant's Army."
Meade also had people in Congress gunning for him, wanting him replaced. Dan Sickles was only one of these folks. Meade was called to Washington to testify before the Joint Committee on the Conduct of the War a number of times to justify his actions at Gettysburg. You'd think he lost the battle by what they were saying.
Meade was a capable general, and a fine army commander, but he wasn't the general who was going to win the war. Grant was needed for that.