The elite in Gattaca weren't genetically perfect (i.e. the upper echelon of a race born by natural chance), they were genetically engineered. There's a big diff

The elite in Gattaca weren't genetically perfect (i.e. the upper echelon of a race born by natural chance), they were genetically engineered. There's a big difference here. Humans are biological computers. There's no reason we can't be made like computers too, with features added that give us the same advantages as silicon machines. In fact it's more likely that silicon machines will become more like us, due to the density, three-dimensionality, power efficiency, and antifragility of our wetware, which is the product of eight billion years of natural selection rather than a century of industrialization. So I think Gattaca is entirely plausible, although it wouldn't surprise me if the oppression ends up happening in the complete opposite direction, where the genetically engineered superior creatures aren't granted human status and instead used as a slave caste by the faith births who wield their unfairly inherited wealth and power.