Among the only differences I could think of, is that noticing the difference between black and white has almost only negative connotation today, while noticing it between males and females is a more mixed bag. What if it was possible to attach positive affect reactions in excess to negatives ones, to that color difference ? Would it still be good to abolish people's noticing ? Though, color of skin isn't a category in the same sense sex is; it doesn't correlate with so much potential difference.

This also leads to the other reason why you'd think it's important to care about difference between sexes but not between skin color, is because the first has practical consequences, for instance, on your relationships, while the other would not.

But while this is true, I can't shake the feeling there is a bias there, which ticks me off. Some people may not feel like gender makes such a difference in how they relate to others. This doesn't back the idea that erasing differences is a desirable thing, but it probably lessens the extent to which the fact that humanity has two sexes adds to life's interest - at least Eliezer should stick to saying he finds it desirable on a personal level, and be more careful about making it an universal.