If I had just read the first part of the story, my unconscious bias would have remained just that - an unconscious bias. It was only by being given additional information that it was revealed.
In fact, you could use the story as a technique to discover unconscious bias. You could tell a hundred people that a young girl was taken and allow them to assume it was a white girl. Ask then how they thought the parents felt. Then tell them it was a young girl from a local tribe in the area and ask them if they adjusted their thoughts on the matter.
I did. The unconscious bias was revealed. And once revealed - once we know that it exists, we can deal with it.
I am fine with the notion of reflection on our assumptions and bias. And I can recall some incidents where I also had a racist stereotype surface in my thoughts, or a homophobic stereotype, and then dismissed it. And I often dismissed it in connection with interaction with people to realize the stereotypes I was taught are wrong.
But I don't think of that as unconscious bias. I think of that as taking all my experiences and realizing some are misjudgments. And some were faulty lessons I had been taught. But they were still my thoughts, that I had to dismiss. I am sure the unconscious makes judgments as well, and those I likely don't realize unless something reveals it.
However, if you believe you can recognize these over time and be alert to them, and learn to dismiss mistaken notions, why do you doubt that someone like Ana can say that, partly due to correct thinking being imparted at an early age, and regular analysis of thoughts, that he doesn't experience those thoughts?
We can't escape the process and the possibility of such bias. However, if you acknowledge improvement is possible, then why are we to think some are not far ahead of others and just aren't dealing with this issue on the same level?
I was raised in a family that was racist. It was only rarely brought up. But it was spoken. I never bought into the overall notion because I lived around people of all races in my neighborhood and my families notions didn't match up to my experience of my friends, acquaintances, etc. Nor did it match up with my faith. And I was blessed to live in a time when such notions were being challenged in society, rather than reinforced. And I too would challenge them with my family when they brought them up.
However, as you alluded to, there were stereotypes I had heard, and would have to dismiss. There were conclusions I had drawn that were wrong and had to dismiss them. And the more you have done that, the less you have to do that, because there should be improvement in your thinking that is more in line with your worldview, values, and in my case, faith. As a Christian I also see God at work in changing my mind.
So I don't see a person as constantly tied to biased thoughts. Once you have gotten past what was taught to you and see the reality through interaction with people, you realize they are all unique, you can't make judgments based on externalities, or group affiliation, and you become better about not doing that. You become more consistent.
And in my interactions with people I don't find it helpful to apply an intersectional filter. If I approach a member of one group one way, and another group another way, that is in itself discrimination. I approach them as a person I want to get to know, along with their experiences. And some of those key experiences to them may have nothing to do with race. Or they might. They may have nothing to do with gender. Or they might. They may have nothing to do with sexual orientation. Or they might. But I can't approach them as an intersectional bundle of interest groups. I approach them as a person. I want to let them tell me their story as they see it, without making assumptions.
We can understand bias in society and ourselves, and historical wrongs, and the current impacts on many areas of life, without approaching someone with those in mind. Because that is its own type of stereotyping.