I'm still not sure what to add. I keep wanting to make clear that it's not the ideas themselves that I object to. Jack turning himself into a bomb and Dean going over the edge for the sake of revenge... those ideas COULD work. There could be some great pay offs there. But the execution isn't quite reaching the goal.
It doesn't help that this is the last season. This is the end, goodbye, the true ending. It has to be judged more harshly than almost any other episode because you only get one of these.
I don't want to compare this to the lead up to "Swan Song" (yet) because I know that's what almost everybody will do, but it's hard not to notice a difference in the emotions. This is supposed to be bigger than season 5's ending, yet it feels like half the weight. I'm still meditating on exactly why, but I think one theory is that the characters felt the weight of the story in season 5, whereas here they feel more like guest stars - even when god himself has shown up to say they're the most important people in the universe.
This is why I caution writers sometimes. Just saying something in the story doesn't always make it so. It's trickier than that, more subtle. Like a magic trick, it's not always about how flashy or dazzling it looks - it's really all about what you can make the audience believe.
Check out my previous interviews and reviews to learn more about storytelling in and around the Supernatural universe!
Thanks to https://raloria.livejournal.com/ for the header image and some of the images in the video.