Earlier quoted context omitted.
Is the (assuming it's true, but it seems plausible) situation that the majority of users searching for "black girls" actually do want to find sexual content instead of simply smiling faces a flaw that needs correcting? Is their intent unfair in some way, are their sexual preferences unacceptable? If I don't like what I see in my mirror, will putting makeup on the mirror improve my face? Will removing naughty sites fr…
So, I'd dance around the issue. Google's search algorithm is "fair", but society is not: It is not "fair" that these search terms are over sexualized. This is, of course, given some particular morality and ethos; your may not find society unfair in this way. (I do) My point is that now it is visible and you can make more informed choices. If you don't like what you see in mirror, why is makeup the "fix" of choice? Al…
After your proposed changes it is no longer visible, and we can no longer make informed choices - people searching for "black girls" still want the same thing, but they're getting a worse service (results that don't fit their intent) just to hide them and their preferences from other parts of the society. There's also a feedback loop in the opposite direction, if there are real problems that simply are hidden, they're not going to get fixed.
On the other hand, it's worth examining the actual problem - it's worth noting that people who do want to find sexual pictures of black girls are just as valid users as black girls, and any fair solution must keep both of their preferences in mind; it would be unfair to simply damage the service for one group to appease the another. IMHO a fair solution would be based on data about what the people who use that query actually want (in some equivalence to picking equal opportunities in the "equal opportunities vs equal outcomes" tradeoff dilemma) - if some people are using the term in their daily search and some are not, then the interests of these frequent users could reasonably be considered more important. Aggressive personalization (different users having wildly different search results for the same term because of the differences in the assumed intent) is another way to do that, but it brings a bunch of other problems.