There is and always will be a hierarchy in healthcare. This does not mean that people should disrespect each other, but the liability usually comes back to the physician hence why they are higher on the hierarchy. This is not a discussion of intrinsic human value but one of workplace roles. Physicians should not be condescending and be so aloof that they do not listen to input of nurses, and I also would not consider a physician to be a nurses "boss" (they have nurse-bosses for that). But the roles of physician and nurse are not equal since the role of a physician has more responsibility than the typical nursing staff. But they are both important so respect should go both ways.
From prior experience the physicians who treat nurses like mud puppies are not good people to work with/good physicians. But the nurses who aim high and think they could run the place better and demand equality to physicians are just as wrong.