The 1970s were 50 years ago. "Long dead", in other words. Did you know that Brazil didn't abolish until 1888? They also imported far more than the US: https://www.slavevoyages.org/static/uploads/01.jpg
It's recent enough that people living today knew former slaves. That's not ancient history at all, so I think the comparison is not good. I'm sure Brazil also has to deal with fallout of their practices, but I don't see how it changes how the fallout of US slavery impacts the US.
And does Brazil have their own 13th amendment that allows them to use prison labor as their modern slave workforce?