Warning: Contains SPOILERS for Chilling Adventures of Sabrina season 4.
Sabrina Spellman dies in Chilling Adventures of Sabrina's season 4 finale, but the ending death creates a plot hole, raising big questions over just why she cannot be revived. After Netflix decided to cancel Chilling Adventures of Sabrina, the show came to a close with its fourth season, made up of eight episodes - each featuring one of the eight Eldritch Terrors. These built up to the Void, a seemingly unstoppable, all-consuming nightmare that would destroy existence in its entirety. Luckily, Sabrina was able to defeat it, but at the highest possible cost.
This comes as a result of the bloodletting ritual performed on Sabrina by her Aunt Zelda, designed to drain the piece of the Void that exists within her. While the ritual is a success, it goes on for too long, and the process is ultimately too much for Sabrina to endure. As the banshee emerges, her fate becomes apparent, and Sabrina dies from her efforts. That Chilling Adventures of Sabrina season 4 killed off its titular character (indeed, titular characters, given Sabrina Morningstar died earlier in the episode) isn't too much of a surprise, but what is more peculiar is that Sabrina stays dead, moving on to the Sweet Hereafter, which is ostensibly a kind of witch heaven.
Everyone is seemingly accepting of Sabrina's death, with viewers getting to see her (and Sabrina Morningstar) being mourned by her family and friends, but that raises the question of why no one tried to bring her back, given Chilling Adventures of Sabrina has established various ays of doing so. The biggest of these is the Cain Pit, a grave in the Spellman Mortuary that has the ability to bring witches buried in it back to life (as seen previously with Aunt Hilda). It's true that the Cain Pit doesn't work if the person is dead for longer than 13 minutes but, even with Sabrina at the Mountains of Madness, there's no explanation given as to why one of the witches (or Robin) couldn't transport her back and bury her within that timeframe, given the powers they have at their disposal.
Similarly, necromancy factors a lot into Chilling Adventures of Sabrina season 4, with Ambrose in particular adept at it. While Ambrose's practices don't extend to fully bringing someone back to life, it isn't outside the realm of possibility that such a means exists, and it seems odd that no one would try given how much they all care for Sabrina. Likewise, there was the matter of rescuing Sabrina Spellman's body from the Void - while it was seemingly frozen from its experience, it's also unclear just what happens to it, or whether or not another soul transference - this time putting Sabrina Spellman's soul back into her own body, which could possibly be healed by magic - would work.
Finally, there's Mambo Marie, who is revealed in Chilling Adventures of Sabrina to actually be Baron Semedi, a loa of the dead. As the person who effectively oversees the realm of the dead, accepting souls into it and also possessing powers of resurrection, then Zelda, given her closeness with Marie, could have asked for Sabrina to be brought back, but again, this didn't happen, and with no explanation provided as to why. The presence of the banshee may indicate that Sabrina had died too quickly to return, but the wailing woman had already appeared in season 3, and did not mean permanent death in that case. Of course, it's possible that there was a plan to bring Sabrina back to life in Chilling Adventures of Sabrina season 5, and that the finale was changed after the cancellation. It may be explained in the comics continuation still, but right now the death leaves more questions than it does give a satisfying ending.