Here is how I see it. There are two kinds of bigots: hateful ones and mistaken ones. There is little you can do to work with angry, hateful people. On the other hand there are people, generally good people, who hold opinions that have been reinforced by their culture. They are not haters, even if they are prejudiced. There are all kinds of prejudice - even (perhaps especially) among those who think they don't have prejudices. We are all learning and growing. "Mean people suck" but mistaken people of good will can grow toward the light and become friends.
Prejudice is inherent in human psychology and can *never* be transcended. It is rooted in how we process data - thinking in broad categories and generalizations. That is the very basis of language - words are generalizations.
People who think they are not prejudiced are deluding themselves and such delusions are dangerous. But we *can* address race, religious and ethnic prejudice etc. and we can try to be open people and to be people of good will.
I am not unaware of the depth of human evil, but neither will I despair of potential for human goodness. It all starts with good will.