If one group of humans (sex, race, whatever) were to be _vastly_ more intelligent than the other, then we may well simply not care about the question at all.
Consider animal welfare. We may care about the treatment of animals to some extent, but the idea that a cow should, say, be able to become a computer science major is laughable. It's not even on the radar.
However, even more, if say, not a cow but a crow (a plausibly intelligent creature) was being helped through the steps of learning computer science, I suspect the reaction would be fascination rather than the anger characteristic of racism.
Indeed, the notable thing for me about racist responses is how far they are from a rational response to hypothetical situation of biological variation between types. The core racist position is overall fixated on avoiding race-mixing yet any animal breeder could tell you that a hybridized type is often a stronger individuals than either antecedent. So racist reactions might be a biological responses then but not responses that strengthens humanity but responses from a single selfish but not superior gene.
That seems quite optimistic. One crow would be a curiosity. A million crows would be seen as competition and there would be torches and pitchforks.
Pedantics aside, it still seems quite optimistic that a hypothetical crow graduating in computer science would be fine with being treated like a domesticated animal. Perhaps it is possible, but ethically that would be uncharted waters.
They used to be treated very poorly, sometimes exceedingly poorly. In the modern era they are generally treated with more respect than they were historically, despite almost everybody having lower expectations of them.
As cruel as it seems to us now, if you're struggling to survive and there's no social safety net, infanticide or child abandonment start to become much more attractive options in comparison with being burdened by taking care of a dysfunctional human for the rest of your life.
(around 70 IQ I think, but sources are very much in disagreement on this, claiming it's more around 25-50 [1]. Taking tests on animals is hard)
Last I checked they were all in the "critically endangered" category [2].
[1] https://www.quora.com/Using-human-standards-what-would-be-th...