Well, not the movie, but the general consensus (with some exceptions) seems to be that the movie is neither good nor necessary, and it’s not on Netflix, so I am probably going to give it a pass.
Some mildly disorganized thoughts on the ending below the cut:
As I see it, there are two possibilities. The first, and more obvious, is that Cooper has been possessed by Bob. In that case, the question to ask about the ending is how and why he was possessed. The more interesting possibility is that Cooper has not been possessed by Bob, but rather has attained enlightenment–but I’ll explain what I mean by that a bit later.
Let’s stick with the first possibility, and with what the hell is going on in those final scenes in the Black Lodge. But even before we get to those, I want to talk about Donna. Donna has been paralleled to Cooper throughout the show’s run, mostly in the sense that they led twin investigations into the death of Laura Palmer, but in addition the show frequently gave them parallel story beats, such as Donna and Maddy’s attempt to steal Laura’s diary from Harold Smith coinciding with Cooper and Harry’s rescue of Audrey from One-Eyed Jack’s, including both getting a last-second rescue from a friend they’d attempted to hide their plans from (James/Hawk). And what is happening to Donna in the last couple of episodes? She’s discovering that she is not who she believed herself to be, not the daughter of Doc Hayward but rather of Ben Horne.
So it is with Cooper. On entry into the Black Lodge he discovers that he is not who he has believed himself to be, the hero and savior, but rather a frightened man who has never stopped running from his failure to do his job to protect Caroline. Caroline, Laura, Maddy, and Annie are presented as blending into each other, shifting from one to the other, because all represent his fear of his own love, his fear that everyone he loves will die. Remember what Hawk said, that the Black Lodge is a place you pass on the way to the White Lodge, but if you are not ready, the Dweller on the Threshold will claim you. Remember too what Major Briggs said, that there are two doors, one which opens to fear and one which opens to love. Cooper succumbs to fear, and in so doing opens himself to be claimed by Bob.
The Black and White Lodges, you see, are the same place. That’s why helpful figures like the Giant and Laura reside there, side-by-side with figures like Bob. Laura, in the end, did not succumb to fear, and so for her (as presumably for the Giant) it is the White Lodge. For Bob and Windom Earle, creatures of terror, it is the Black Lodge. And so it becomes for Cooper. The more frightened he becomes, the more terrifying and incoherent the Lodge becomes, until it finally consumes him.
Or perhaps not. Perhaps the Black and White Lodge are the same place because there is no difference. Perhaps that was the White Lodge, and what happened to Cooper was enlightenment. This is, after all, not a human universe. There is no reason to expect enlightenment to look anything like human morality. Cooper passed through the heart of the world, descended into the abyss, confronted his own shadow selves Bob and Windom and maybe Laura, and at last dissolved. What emerged was not Cooper, but an enlightened soul, a thing shaped like a human being but containing within only Truth, which is to say the Lodge.
Either way, one thing is clear: Briggs’ fear came true. Love was not enough.