Because science is a branch of philosophy and machine existence brings plethora of unanswered questions.

Imagine humankind meets another race, another race shares it's scientific knowledge and humans accept it without experiencing process of discovery. In that case do we really got this knowledge? If we follow machine discoveries like we follow problems in textbook then we acquire knowledge but we don't discover anything. We follow.

There whole lot of philosophical questions that aren't attacked now. Are complex systems sentient because consciousness is emerging behavior? Then should they have rights? Philosophy is part of humanities and science (is/used to be) part of philosophy. Should we accept non-human knowledge in science? Maybe it's altogether different thing from science, yet very similar.