A little discussion about the brothers then we’re in the home stretch for this wretched season.
Ask me to sum up the brothers in this season and setting aside the “true villains” joke from the previous part, it would be “passive” or “plot device.”
Note that “active” and “passive” here can get confused with the “act/react” dichotomy of villains & heroes. But in a story, a reaction is still an ‘active’ direction for a character as long as a character is aiming to accomplish some goal. Think of it in a scene where one person shoves another. The one who instigates is the one that starts the act. The one shoved can react and push back, making them active, or they can just go along with the shove and proceed in that direction, being just passive to the event*.
So even when looking at past seasons, where the brothers had to react to the machinations of Heaven and Hell, we can see that while they were not the instigators of the plot, they were still active forces in driving the plot along. (as pointed out previously by njspnfan) With this season, where are the brothers active? Sure they did things but where was the motivation? What was their internal drive?
Dean is only active when he calls out to the angels to help his brother. After that he is pushed around by events and the scripts with very little indication as to his goals and motivations. No really, go read some transcripts of scenes where you think Dean must express his goals and you’ll see he’s almost politician-like in dodging concrete answers.
Sam at least has a bit longer period starting when he fights back against Gadreel, then kicks Dean out of his life, and ends when he and Castiel try to find Gad. After that, it’s mostly again going with the currents. Heck despite being the one more wronged by and with a larger grudge against Gadreel, when the angel appears in the bunker at the end of the season, Sam’s not the one who attacks, Dean is.
On an episode-by-episode scale the brothers do show some signs of activity when they get to go on a monster of the week hunt. But these are all moments largely unrelated to the arc of season.
Don’t get me wrong, there is at least some logic to it: if everything you do makes things worse, the first step is to stop doing anything. But we never see any reflection on these moments. We never see signs that they are making an effort. The closest is a scene like, “Dean is drinking in a bar alone.” Is he thinking on what he’s done? Is he thinking about donuts? Is he thinking about which pony is best pony? (all hail fluttershy!) Is there any sign that Dean is going to change his ways and be less reckless? Nope, immediately afterwards we see him do one of his most reckless things ever. Again the show is having the audience do the work of inventing what’s happening rather than do the work itself.
Which brings us to the final part of the season which so often pushed the boys around: Ezekiel/Gadreel.
Gadreel is, with some irony, the most active and consistent character of this season. Part of that is from the writers establishing him as being a bit of a dunce; so any inconsistencies of character this season can often be written off as “aww, he doesn’t know any better.” Yet throughout he is constantly working to accomplish something – anything – to redeem himself even unto death in the end.
By the end of the season, Gadreel had a character arc, which means he is the arc of S9.
Meanwhile the boys end the season where they began it. One of them dead/dying because of something with their forearm. The rest of the season, is just a waste.
*Of course clever authors will play around with this and it can be changed up. “Going along” can be revealed as being active if the shovee leads the shover into a trap for example. If, however, the shovee is pushed because it’s known they’ll shove back (think of pretty much every bar fight scene ever) that reduces the shovee to a passive role. But this all gets deeper and deeper into the fictional world and its construction.