Lee’s strategy at Gettysburg was a mass attack against the center of the union position. It failed. Who gets the credit(blame)? The general does.
...Lee was forced into that stratagem by the failure of both his wing operations, due in no small part to dilatory actions by both commanders...the opportunity to force Meade to withdraw towards Washington was palpable the first two days at Gettysburg, and was frittered away, with reprehensible carnage the result...
Nonetheless, Pickett didn’t care much for Lee down through the years, did he?