There is a flowchart:
It's every big decision you can make that gets you to a different ending. Some comments on this chart include little criticisms for missing out on two endings, naming the endings weird, and one person who says "feel like this game need to be longer." Most are just impressed with the presentation, commending the author for the amount of work that must have gone into this chart.
I recall reading old-timey maps for RPG's. Pokemon Diamond and Pearl's strategy guide artfully printed out full routes and marked where every single trainer, patch of grass, and hidden item was. Banjo and Kazooie's guide goes above and beyond with an isometric view of every single section of the world.
Sicart highlighted a sort of dichotomy inherent in building decision into videogames: we want the gamer to act as an ethical agent making decisions in a simulated world, especially when we want to explore literally any concept involving choice and consequence. However, the player might come in with the idea that they are an explorer, and as such, they should have the freedom to know a great deal about the world they partake in through their avatar; they should know what each character is going to say in response to a dialogue choice, they should know where to go to progress in a certain way; they should have the freedom to pursue a desired ending and then retry if things go wrong.
When looking back up at that chart, it's hard to conceive of a game where both of those ideas can exist harmoniously. Stanley Parable challenges the entire endeavor of completionism and goal-pursuit, but for someone who just wants to get in and find all of the different endings, they could just look at this chart and trace their way to whatever ending they wanted.
A game that lets you play it only once skews things towards more ethical consideration in play. Decisions actually become linear in time; you only know what you've already been through, and you're never going to go back and deliberate with more information. In a sense, that might completely turn off people coming in with an exploratory mindset.
We could argue that this is the point. In real life, there's always a small voice in my mind asking me to do things "just to see what would happen." Standing on a bridge? Just jump off and see what would happen! Bottle of apple cider vinegar open on a table? Take a shot! Normally, that voice goes unsatisfied, since most of its suggestions aren't really good ideas. Sometimes it does, in fact, get satisfied. It's satisfying to just do things to see what happens sometimes, is what I'm saying.
This "what if I did this"-ism drove me to do my best to follow along with the narrator's instructions, then slowly work backwards from the "total-obedience ending." Ironically, the first ending that you get with that method is the one where the narrator gets to have a big monologue about how Stanley doesn't actually have any power in his situation. In the midst of frantically pushing buttons which the narrator admits are useless, I started wondering: Stanley Parable kind of is a game about considering ethics while also rewarding exploration. You get cool writing for going off into different places and doing weird things, but you also get yourself thinking about non-linearity and the "story" (if there even is one).
What would a game that decouples the two be like? Are there games out there that have immense replay value with large amounts of opportunities to repeat that, even on one's gazillionth playthrough, keep you guessing and thinking about what to say or do? What sorts of features would such a game have? I'd imagine a randomized story structure might help. Completely random characters? Who knows.
So I find this a really interesting question because I think that games already exist that as you say "have immense replay value with large amounts of opportunities to repeat that, even on one's gazillionth playthrough, keep you guessing and thinking about what to say or do", but the distinction lies in the genre of the game. Some tycoon or worldbuilding games, like say the Football Manager series or the Civilization series, have essentially infinite ways that each game could play out and even attempting to optimize your playing only increases the chance of your preferred outcome, it does not guarantee it. So I think an important caveat to your question is whether or not this would be possible withi…