Natural financial (and non-financial) incentives, by which I mean those incentives that are part of the model in which you're observing bias, do probably reduce bias, by letting less-biased actors win more. Artificial incentives from outside the model can alter behavior, but not directly change the rationality level.

Many biases are self-serving enough that they'll alter to match the behavior that outside incentives cause. I'm not sure that counts as a reduction in bias, or just a shift to biases that the incent-or prefers.