I don't really care the content at all, but I really wish these platforms took the "phone company" approach, in which they considered themselves neutral carriers of information. In the US, I don't know an obvious issue besides legislative change to enforce this. However, once they consider themselves as "curators" of information with near-monopoly status, I hope they are litigated against successfully.
The opportunity to be a neutral carrier is sacrificed by any platform that deploys a recommendation engine. Recommending content is a form of curation, which makes them a publisher, conceptually. It does not matter if the content curation is done by hand or by an algorithm that was built by hand.