The only way to kill 500,000 people practically is to do it by the letter of the law. Murder (especially for money) doesn't scale without being a state or quasi state actor, or something on that tier.
The Nuremberg trials were a slap on the wrist compared to what the collective perpetrators, beneficiaries, and active agents of the war and the associated genocide deserved.
The broader cultural impact of them (and of the war guilt) imposed on Germany landed fairly well, though. Unfortunately, it is possible that it might have landed less well if the punishments actually fit the crimes.
Observe and contrast it to Japan's take on its war guilt, and its less-than-enthusiastic attitude towards taking responsibility.
