Actually, I'm gonna add the comments I had originally left in the tags and expand further:
#OP talking about “paying homage to the original writer's legacy” made me laugh because like. that's the opposite of what S3 did#S1 already established humans have free will (see Adam picking humanity over fulfilling his destiny)#and I doubt Pratchett would like the idea of nuking the whole entire world because it's imperfect and we might as well start from scratch#the whole point is embracing humanity#“let's make every single person's life as they knew it end without a say in the matter” is not exactly a humanist message about free will
I think it's quite telling that criticism of the finale is often reduced to "just people being mad they didn't kiss"; because I truly believe the only way to enjoy this finale is to not care about Good Omen's narrative and themes beyond Aziraphale and Crowley's relationship.
Because on a surface level reading of the plot, if you're seeing Crowley and Aziraphale's relationship as the sole focus of the series, the finale is fine. They get to spend their life together in another universe, falling in love and growing old without having to hide their feelings for one another.
(And there is a point to be made—like prev does—about how those aren't the real Crowley and Aziraphale, because everything that made them who they were—their memories and their experiences—was lost. And I agree with that analysis, but it's beyond the point I'm trying to make here)
However, if you consider what it means for the broader Good Omens universe, the finale is straight up a betrayal of the ideas expressed by Pratchett in the original material. Good Omens has always been a story about larger than life supernatural beings falling in love with humanity, but one in which ordinary people are just as prominently featured as angels and demons. Crowley and Aziraphale are not the true protagonist of the story, humanity is. This is why the story culminates in Adam refusing to take part in the Divine Plan and choosing humanity instead. The S1 ending is both about how humanity is worth preserving and about human agency. No one, on either sides, expected Adam to oppose the divine plan. Because they didn't understand Adam would have agency over his life and what he wanted to do with it. They didn't even consider he could choose humanity.
The S3 finale expresses the exact opposite message. The fate of humanity is not dictated by humanity itself, but rather sealed by a handful of divine beings that treat their lives as an afterthought. Crowley and Aziraphale are incredibly OoC throughout the whole fianle, but their final wish to god is particularly aggravating. The original material expressed several times that the idea of giving up on people and create "new ones" is not an option, so the idea of the two of them suddenly deciding it's the right thing to do is extremely poor writing. It's justified as a way to give humans "free will", but it was already established in S1 that they did, so that doesn't even hold up. And I know that them asking to just bring everyone back would have been (rightfully) criticized as bad writing, but the solution here would have been to just.. not write themselves into a corner in the first place.
In the last 10 minutes of the finale the writers undid everything that was previously established in the series. Crowley and Aziraphale never fell in love with each other through the centuries. They never banded together to stop the Armageddon. They never raised Adam. Agness Nutter never prophesized Anathema would save the world. Newton never became a witch hunter. Adam never chose his friends and his human life over the divine plan. Gabriel and Beelzebub never fell in love and ran off to Alpha Centauri together. Those lives and those experiences just disappeared forever. We see that things are working out for the reincarnations of Crowley and Aziraphale. But what about everyone else?
