Just so you know, when you say something is impossible, you have people like me who like a challenge, despite being very aware of how difficult something is. 
But in general, I do agree with Mara. It just doesn’t stop me wanting to give it a shot at simulating a world, even if it likely never amounts to anything. Partly for myself and partly for others, even if it wouldn’t be appreciated by many. But a feasible project needs to come first for financial reasons.
And yeah, it is of course impossible to simulate a world where you can sit there and just watch an NPC go about their life or whatever. Or at least if you want it to be even remotely interesting, because you can only read the same text so many times and we can’t drum up infinite amounts of text. The only real way to simulate it is to create a time variable, use a hub system, and have certain NPCs/events appear or happen at certain times, while providing options to ‘live your life’ so to speak, like letting the player gamble. It’s just . . . unfortunately, a mammoth task, one best suited for multiple writers, and even then . . . it’s a lot of work for each individual.