The term "fluff piece" usually refers to a news story that deals with a relatively unimportant topic, something light in tone, something considered extra.
This YouTube video happened to be one of the several clips that popped up as recommended, so I'm not quite familiar with the context of this discussion, but apparently, the interviewer seems to be asking him if he isn't just treating the documentary he made about suicide prevention as a fluff piece in the hope of boosting his favorability rating or something back up.
The only term that comes to mind is "un reportage bouche-trou", but I'm not sure. How do French speakers commonly express this idea?