Don't need to dig in. Just destroy factories, electrical transformers, oil infrastructure, and train yards.
Sure you still have innate/learned biases but eliminating situational (recent divorce) and bodily (hunger/sleepy/horny/sick) bias entirely is still a massive reduction in the total amount of bias you face day to day. If anything being able to see the biases of the data going into something like NarxCare is a good thing because now you have a paper trail for improvements. You can't just grab a hundred doctors and ask them "have you ever denied care due to your biases against women?" because the bad ones will either lie or not realize what they have done.
It is irrational but the same sort of irrational everyone is. Monkey need to survive winter so monkey stocks up on food/resources. Monkies never needed a ceiling for this behavior as there was never enough food. Now you have apes with a billion winters worth of stockpile yet that voice in their heads is still as loud as ever.
This is why automation is good. Humans can't be trusted to do critical jobs such as doctor, lawyer, cop, teacher, or judge without being influenced by a bad experience they had a decade ago, what they ate last, their pending divorce or how much sleep they got last night.