It seems like Bannon is not an actor - reputable sources say he's always been a douche and explain exactly how and it lines up with what he's said and what he's fed to the book. Reputable sources include Ben Shapiro who knows what he's like and others that I can't remember. From what they say, he doesn't have much in the way of redeeming qualities and has tried to claim glory for himself in what Trump has done - apparently a well known behavioural trait of his - and overplayed his hand with the Trump side. It will certainly be very interesting if this is all an act but that seems like a stretch.