Since most major TV stations are owned by corporate interests it makes sense that their primary role is to protect those interests. It's politics. The media moguls and powerbrokers have no intention of serving the public by offering programming for the "public good".
They will mobilize public support for their interests ahead of any other interests that would get in their way. Sponsorship plays a role in the retention of the media special interests by financing them.

I think Chomsky is right on.