That is a narrow and incorrect definition IMHO. Two resource constrained solutions can also differ wildly in their rationality (or reality approximation if you will) and there is no resource unconstrained general intelligence in the universe so we wouldn’t even really know what that normativity looks like.
Biases are more of a classification of errors specific to our cognitive machinery; framing errors, recall errors, precision errors, proportionality errors, inference errors etc wrt the best we could have done with it.