"Judging [the] past by current standards" sounds like the person you were talking to may not have cared so much about Napoleon, as much as they care about all the cheap statues of literal Confederate slave-owners and defenders of slavery that got reactionarily dotted over the American South. There's been a big movement over the past decade in America to tear them down (IMHO, rightfully so) and a lot of people consider that "rewriting history" (which is rich considering the history of the Lost Cause).