that would be quite the challenge for dev to do too, since this isn't just one quest from the guild but this is a chain quest, from the nun to the guild house. So if it is "one and done" then it would be extremely taxing to program.
I know. I have seen this becoming more common innon-isekai mmorpg series. Where either due to programming or the whole world turning out to be a real world that people unknowingly or knowingly connect to and act as strange adventurers who just magically appear and disappear while being unable to permanently die.
They seem to have this idea of a fully realistic world where the NPCs have complete agency within set limits about having or no limits. I could see the programmer just programing in things the NPC cares about or wants and letting the AI go about doing these things or making a quest for the players to do it for them. I could see it being that the Cleric woman was going to mail the note but the AI realizes that it can just give her a mission with a reward to this player and the letter will be delivered.
This reminds me of another trope with NPCs that can permanently die despite being quest givers or where random events can happen that can cause NPCS wars or fall of the kingdom the player is in. I know one anime started with the Main Character running into an npc Knight, that is a major power in the kingdom he starts the game in, randomly running around asking a player to help her find her lost sister that he does take. It's later pointed out that if he hadn't taken the job the knight would have gone on to do it without a player and most likely die with her sister permanently from the game. Granted the ending of the show hinted that this really was an isekai that all of the players unknowingly jumping into and back out of a real fantasy world.
My issue with this is even if you have programmers willing to do this, I don't think this sounds like a fun way to play a game. Where you could randomly miss an amazing quest or find out the NPC you have been working with for weeks long quest got killed while you went to bed for the night.