Given his skill at manipulating the press, it’s totally understandable why Steve Bannon would agree to or even embrace being the subject of not just one but multiple documentaries. But where Errol Morris’ 2018 film “American Dharma” aimed to interrogate and deconstruct Bannon’s poisonous philosophies head on, “The Brink” embeds filmmaker Alison Klayman (“Ai Weiwei: Never Sorry”) in his daily life for months on end, observing his methods, and eventually, exposing the efficacy of tactics that have rhetorical foundations built on quicksand.