Frontline really is a terrific news program. I'd like to do more research to understand why publicly funded stations (notably PBS/NPR) are so much better at doing real journalism than modern for-profit companies are.
The obvious answer is "the for-profit companies have to cover whatever makes them money," and that's true as far as it goes, but do note that publicly funded news organizations also need viewers/listeners who are willing to donate money directly, so they aren't entirely removed from the need to pander, either.
The difference is pretty obvious: publicly funded endeavors are fine as long as they can cover their operating costs. When you've got shareholders, it's a different story.