The corporate media at large will never support a guy who's policy positions are predicated on higher corporate taxes. No one wants to pay more and no publicly traded corporation's leadership is going to publicly advocate that their own shareholders face the effects of higher corporate taxes. The establishment has a vested interest in maintaining the status quo and their propaganda arm, the media, is trying to convince people that the social benefits will not outweigh the additional tax burden.
If the media seems to be doing Bernie dirty, the reason is profit motive. I doubt it is personal. That being said there are specific media members who are in the tank for either candidate but the directives coming down from the top are definitely pro-business and anti-socialism and who can blame them for that?