Yeah, but it was pretty obvious who were the former slaves. There was no "nuance" about it. When the tell-tale signs aren't physical, but small, subtle differ

Yeah, but it was pretty obvious who were the former slaves. There was no "nuance" about it. When the tell-tale signs aren't physical, but small, subtle difference, they are easier to erase. You can change your name, religion, what you eat, and how you talk. So if those are the signs of your ancestors' caste, they probably won't last for generations in the west unless there's a conscious effort to preserve those distinctions.