It seems that there is more than one applicable technique to this quote. Consider irony and intertextuality. In "Hag-Seed", the character of Caliban is represented collectively by the prisoners. Unlike Shakespeare’s Caliban, the characters of WonderBoy, 8Handz, Red Coyote and the others fully utilise their new understanding of language to find their voices; empowering them to gain respect. Thus, they are given an opportunity to feel as though they are of equal worth in society as anyone else. Atwood utilises extreme contrast to further highlight the 'progressiveness' of equality between the 1600s Jacobean era and present-day society.
Additionally, there is the notion of hyperbole/exaggeration, whereby Atwood exaggerates the idea that they have never been loved to enforce upon the reader the fact that the prisoners are mistreated from birth. Most of them have been raised in a society where their fate has already been destined. They are imprisoned from birth.
I hope this helps!
