Whereas the opposing view would be,
you've been pulling nearly all the strings, all the time.
I don't want to dismiss the emotional payoff, because that really is rewarding. But I think
@hawkeyefan points out pretty astutely with his dragon behavior example that the GM isn't just "extrapolating", (s)he's determining all possible baseline details that presuppose the extrapolation.
One could reasonably ask,
what's so special about the players having that reaction to your specifically curated set of string pulls? Is it less rewarding if it's someone else's set of strings?
One of the more compelling things I discovered with Ironsworn was that I-as-GM actually got to start having some of those fun, "Oh my gosh, how cool is that!" moments myself, and it was at least as rewarding to have those moments with my players at the same.
This goes back to
@loverdrive 's comment about "all things ultimately being reliant on GM restraint". I regularly struggled in GM-ing trad play with the notion of, "Well really, if the BBEG is really as powerful as I believe (s)he is, and the PCs really are mucking with her/his plans as much as they are, isn't BBEG going to eventually just go nuclear and drop an army of 50 liches and 50 balors on them at some point and just be done with it? And am I being untrue to 'the simulation' if that DOESN'T happen?"
I'm very, very sympathetic to the goals of sim. On a certain level I, even to this day, find it an appealing idealization.
But at some point, I've had to reconcile the idealization against what I saw and felt when GM-ing in a "sim" fashion, which was,
Don't fool yourself, despite your best intentions, you're pulling far more strings and exerting far more will on the outcomes of events than you want to admit.
3/4 of the way through a 20-month Savage Worlds campaing---one of the better campaigns I've ever run---one of my players came to me after a session and said, "You're kind of just making stuff up so we can keep playing now, aren't you?" And he said it with a smile, completely non-accusingly, but fully recognizing that after 20 months of endless "extrapolating" and "string pulling" to maintain "fidelity to the game world", that he and his character were really just along for the ride at that point.