That's not "the point", that's how a lot of traits work and it's the reason males have so many more defects and health problems than females. For any given defect on the sex chromosome, females have a backup.

Now gathering is the supposed reason for females seeing more shades than males. But I've questioned several people and haven't found any difference at all, so chances are it's bullshit. Probably just men not paying attention to small details even if they can see them. Although it's possible I have more female-typical traits in this area. I can say I definitely would've been a gatherer, I could never handle hunting.

If they had been lacking in these attributes, the tribe would have starved. Color vision would have been wasted on them.

See with males, it's always about how they can benefit the tribe and nothing else. But the females' own wellbeing and dignity is considered important. As ironic as it is, the female design seems tailored to individual needs, whereas the male design is tailored for collective needs. This is what I mean when I say nature treats males like trash. They don't matter to nature, only their usefulness does.