I understand what you're saying, but I don't think such people's hateful opinions should be counted when speaking about such things. There are always going to be people who do not think murder, slavery, and torture are not wrong but right. They are a small minority and while it's important you make note that such scum and their opinions exist, it's also important to note that they do not represent a significant portion of people either in number or in strength of opinion. There will always be outliers but I'd say most people and all decent people agree that slavery and the nazis were both wrong.