The thing that made GOT really work was its cast of interesting characters, including a number of the more peripheral characters. In the last season, the focus was on the main characters and wrapping up the plot. I don't think the writing was that bad per se. I think that so many interesting characters were killed off and sub-conflicts resolved by this season, that we were just left with a thinner cast and fewer story lines. So then they turned up the cinematic production in order to compensate--making it less story and more effects.