Josh Larsen’s review published on Letterboxd:
Another look allowed me to focus more on the alternate reading that's suggested by the title. (Spoilers ahead.)
You could make the case that Glass dies shortly after he lies down next to the body of his dead son. (There's a particularly potent cutaway shot to the sun piercing through the cloudy sky.) From that point on, Glass is a specter haunting this land and the people in it - he resists "letting go" and following his wife and son into the afterlife because he instead chooses revenge. And as long as he does so, as long as he ignores their calling to him in those visions, he's cursed to live in this in-between space (hence his ability to survive the most arduous of hardships and incidents). This reading inverts the ending too. I never bought Glass' release of Fitzgerald as some sort of relinquishing of revenge. Fitzgerald was pretty much dead by that point, and Glass was sending him to a certain fate in the hands of the Rhee. So he's still a vengeful man at the end. Notice Glass' final vision: his wife turns away from him and although he smiles, he doesn't follow. He looks at us instead, haunting us, because he's still a man of vengeance, and therefore cursed.