Sorry but this is not helpful.

Slavery was wrong then and it is wrong now. societal consensus cannot be excused because it was in the past.

Highlighted and rightfully acknowledged but slavery cannot be simplified to just forced labour when rape, murder and unethical experimentation was also performed. I think it’s incorrect to assume that this should not be criticised with the standards of today as to do so is to ignore that it is a very human issue to value the life of another so poorly and assume we were all barbarians only 300-400 years ago which is not the case.