When you say unconscious bias, you are kind of implying that the model learns something that is false. But more often it's the case that the model learns something true that we don't want it to learn. That's what makes the problem so hard, you are trying to hide the truth from a system you only half-understand processing data you only half-understand. There is a big risk the truth slips through the cracks if you aren't careful.
It's more that the model learns something that is undesirable. It could be the case, for example, that the true thing that the AI learns is that your resume screening process tends to exclude women. This is true, sure, but it could lead to the undesirable outcome where the presence of a female name on a resume might be weighted heavily against the candidate.
I agree that this process is one of resolving blind spots, but I disagree that the blind spots are simply areas devoid of light. AI/ML systems are frequently employed to augment or stand in for human perception, which is known to be necessarily incomplete with respect to reality. In other words, they can learn things that seem true to us but that are false from another perspective, or undesirable once exposed. What's exciting about them is that they provide an opportunity to interrogate the flaws in our individual perception with a systematized observation and analysis, in a much more sophisticated manner than in the past. But fulfilling that potential requires humility.
https://www.wired.com/story/best-algorithms-struggle-recogni...
Their failure was not just in lacking diverse training sets, but diverse QA, or at least QA looking for those blindspots which eventually became evident.
So, correct, it's not as simple as having "sufficient" data.
Your expectation was the same one they had, and it was wrong, which is the crux of the issue.
If you asked the developers of the facial recognition library, "does your software have problems with very low contrast conditions" they'd surely have answered yes. Fully conscious of the issue but, that's software. It's hard to get everything right 100% of the time.
Do you have a source for data set mis-labelings being a problem?
However, ML is often sold as a solution for generating outcomes, not for finding truths, wether they be true or false.
The distinction is huge.
No matter what humans do, they will reap what they sow. Consequences and outcome matter more than "truth" (which may be in the eye and competence of the beholder).
If the results are odious to us, it should be impetus to critically analyze not only the AI/ML systems, but also the underlying assumptions that they're built on. Instead, developers become defensive and cage-y about their processes.
If you don't want systems to have disparate impact, you have to be adamant about it in your design. If you think society is better off with systems that reflect preexisting biases, then fine, but be ready for the backlash.
At the end of the day, it really is up to what humans want to do with themselves. It's an opportunity to be truer to our intent, not a bug to be covered up.