Many cultures have a simple "You are not guilty of crimes other people committed" rule baked into their law and culture to accommodate this, because what you're

Many cultures have a simple "You are not guilty of crimes other people committed" rule baked into their law and culture to accommodate this, because what you're describing is also just known as "history." In general, most people have at least one near ancestor that did something terrible. That makes none of the descendents terrible people.