It is worth noting that credit scores don't necessarily eliminate bias, it just adds another step. It wouldn't surprise me to learn if you could predict an individual's credit score based on non-financial facts because some of the old biases were cooked into the system (by proxy or not). (I very much suspect this is true but don't have it in me to go hunt down papers right this instant…)

An improvement over arguing your case with the teller, yes, but not necessarily flawless.