I think you took OP the wrong way. Bacon doesn't say knowledge has to have utilitarian value. He says that something only IS KNOWLEDGE if it can predict an effect. He was arguing against the many theories of people before him like Aristotle who said a bunch of things that sounded reasonable but were actually purely speculative nonsense, no matter how reasonable they sounded. In so doing, Bacon was establishing the foundations of induction and criticizing the long history of deductive reasoning.