The views in my comments are no more reductionist than the parent comment I was replying to. I would also suggest that rejecting psychological egoism as reductionist is a rather blatant anti-science point of view.

However whether reciprocity was involved doesn’t at all change the existence of a self-interested motive. It’s simply irrelevant.

Furthermore, in this case there was reciprocity. In this instance the big corporate interests were selling a product for which doctors had a demand to treat their patients. You’re welcome to have an opinion about the integrity and value of that reciprocity, but that goes for anybody in regards to any relationship. A cynical person could come to that conclusion about any relationship, and offer you a justification for it supported entirely by a leading thesis from the field of ethics.