The film, like the interviews themselves, doesn't really get up to speed until the end, and then it's over. Of course, we saw the money shot (I mean, line) in the trailer. So that's a non-starter, dramatically. "If the President does it, it's not illegal."
In fact, the only things in that are in jeopardy are Frost's personal financial situation and his career. Assuming we, the audience, care about either -- which is a big assumption because there is little to get us emotionally invested in Frost -- it's hard to judge just how much jeopardy there is. Is he really going to be bankrupt if the project goes poorly? The film is as cagey with us about such details as Frost and his cohorts are with one another about the same topic. This means we don't quite know enough to even understand the gravity of what his accountants may have been telling him.
And from the views we have into his other television activities, one might surmise that the world would have been better off without those programs. Which is to say, we have so little reason to like Frost, that it actually makes Nixon look better than he should. Which may explain why the Nixon library, and everyone involved with the former President, supported the film with open arms.
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Reader Matt makes a good point about the drunk-dialing scene. He's right. That was by far the most interesting and revealing and meaningful and insightful scene in the film and arguably the only "fabrication" in the script. It's a clear case where making up a story conveys more truth than simply recounting what happened.