I think that once the players decide what Point B is, and get there, that (probably) becomes Point A'--and I don't really see a way that makes sense to say the GM "created" that, since it's where the players have taken the game. I think this is where I at least am not seeing a conflict between "story" and "play." By playing the game, the players shape and direct and establish and define the story.
It's possible that I'm misunderstanding what you mean by "story curation." I mean, effectively, deciding what the story is about. Someone at the table decides on the characters' goal/s, and (I'd argue) the story that emerges from play is about the characters' pursuit thereof.
Based on these two quotes, you (prabe) seem to be using
story to mean
the sequence of imagined/fictional events that unfolds in the course of RPG play, and seem to be using
curation to mean
deciding some of the content/topics of that story.
Used in this way, all RPGing produces story and all decisions about framing and consequence narration are story curation.
The way that I,
@Campbell,
@Ovinomancer,
@Manbearcat and (I think)
@hawkeyefan - maybe other posters too, but they're the ones who spring to my mind - are using the words is different. In particular, we are using them in a way that does not entail that all RPGing produces
story (I think
@Manbearcat and I have put the strongest emphasis on this) and that not all decision-making about the content/topic of the fiction is
curation (I think
@Campbell and
@Ovinomancer have put the strongest emphasis on this).
Taking these in order:
When I talk about
story in the context of RPGing, and when
@Manbearcat in the OP refers to a
storytelling imperative, we are using "story" in the fairly common sense of
a narrative with a recognisable pattern of rising action, crisis/climax, leading to resolution and denouement. Of course there are infinitely many variations on this pattern. But there are also ways to string together events that would count as a story in the bolded sense I have attributed to you, but would not count as a story in the current sense (ie the sense in which I and
@Manbearcat have been using it). The campaign I suggested, of module B2 followed by X1 followed by X2 followed by S2 followed by S1, is extraordinarily unlikely to produce story in the current sense. In the TV show Red Dwarf, part of the joke about Rimmer's Risk diary is that a recount of a game of Risk - while a recount of a sequence of fictional events - is not a story in the current sense.
In the history of D&D one can identify patterns of play which do, or don't, care about producing story in the current sense. Lewis Pulsipher wrote about them way back in the late 70s. In published adventures the publication of the DL modules is widely seen as a turning point; there are also interesting "intermediate forms" like Hickman's Pharoah and Ravenloft which are at their core dungeon crawls of the classic form, but are also intended to have not just superficial trappings of a story (as X2 Castle Amber does) but to actually produce something story-like in the course of play. (I've never played either and so can't comment on how successful they have been; my reading of Pharoah makes me have zero personal interest in running it, though.)
Of course any poster is free to use a word like "story" however s/he likes; but the difference in patters of play that I describe in the previous paragraph is a real one, and it is helpful to have a term available to describe it. In my own posts I do this by using the word
fiction or the phrase
fictional sequence of events to describe the stuff that is inherent to all RPGing and differentiates RPGs from boardgames and at least some wargames; while using the word
story to refer not just to a fiction, but to a fiction that instantiates that typical pattern of rising action, crisis/climax and resolution/denouement.
Turning now to
curation:
When
@Ovinomancer or
@Campbell uses the phrase "story curation", they are talking about making a decision for a particular sort of reason.
Curation, in this sense, is a particular type of intentional act. I think it was
@Ovinomancer who in a post upthread drew the comparison to curating an art collection: the intention is to achieve a particular aesthetic presentation or result. In the context of RPGing, the sort of curation they are referring to as
story curation is making decisions so as to achieve a particular story result. Examples might be
so as to achieve foreshadowing of some anticipated later event or
so as to ensure that what happens next will be climactic (this is of course quite relevant to the OP). We can also imagine "negative" versions of this - making a decision
so as not to negate some earlier intended foreshadowing or
so as not to produce anticlimax (again this latter is quite relevant to the OP).
There is an approach to GMing which emphasises having regard to such reasons in making decisions - whether framing decisions or results/consequence-narration decisions - about the content of the fiction. But (contra
@Crimson Longinus, if I've understood that poster correctly) that is not the only approach to GMing that has existed in the history of RPGing, or that is possible. There are other approaches, and some have been described in this thread by me,
@Campbell and
@chaochou.
It's also worth noting that there are ways of
designing an RPG which will tend to ensure that, in the play of the game, story-like elements (foreshadowing, rising action, climax, resolution) will emerge
without the need for curation. Generally they eschew the sort of "naturalism" that
@Manbearcat and I have referred to and that I posted about upthread in reply to you; perhaps for that reason they do not have the market share of 5e D&D. But they also sidestep the tension that is described in the OP.
But 5e D&D is not one of those RPGs; one feature of it that makes that so is its reliance on "naturalism" rather than overt allocation, among the participants, of responsibility within parameters for the creation of the fiction at various points of play. Hence it is at least moderately unlikely to produce
story in the sense that I am using that phrase without curation; and as the OP notes, that curation - which mostly works by the GM exercising his/her extensive authority in respect of as-yet unrevealed backstory/offscreen fiction - has the potential to negate or undo the gains of skilled play. Hence the tension which prompts the question in the OP.