Because they have all adopted the online, social media based publishing model a.k.a. fake news:
Profit-centered coverage means that the media wants you to get emotional about stories. They want things that will get people arguing and get your blood boiling. They didn’t investigate Dr. Dao’s background because it was responsible reporting, they did it because it had the potential of increasing profits on this story. They didn’t skip over the contract issue for days because they were lazy, they did it because they thought the story was more profitable if people could engage in the standard left-versus-right story angle that is the core of their profits right now. A story that is too clear-cut on one side is over and done with quickly. A story with an argument in it can stay alive for weeks.