I didn't say the AI should be unbiased, just whoever writes it.
I want an AI that is biased to the truth when there is an objective one, and my tastes otherwise. (that is when asked to find a good book it should give me fantasy even though romance is the most popular genre and so will have better reviews)
I'm not sure the idea of a sentient being not having a bias is meaningful. Reality, once you get past the trivial bits, is subjective.