yes, and I can point you to a rule that says DMs can override other rules...
Yes, I know that. I've seen them. And I've already said, that's fine... it's a perfectly fine way to play.
But it renders player agency non-existent.
For player agency to exist, the DM must be obliged to honor player input.
I've said that as well. With a bit more specificity. Saying no doesn't inherently remove agency, just the same as saying yes doesn't inherently grant agency. Both yes and no can affect agency or not, depending on circumstances.
Do you think that agency is something that can be given? Don't you think that's inherently paradoxical?
Nah that's a cop out. This is just hand waving without actually explaining how this fits into the world fiction. The PC marches up to a palace guard who is, what, a low level type of genie and demands to see the king? And I am to believe that a common elemental guard is going to care enough to go through all the work to help someone who he probably thinks is insane contact the king? So that the guard can be executed for dereliction of his duties???
Anyone is free to run their game however they wish - obviously - so much of this is moot. But for me, in my games, things follow the PSR. They don't just happen for no reason or without some coherent explanation.
I can imagine any number of ways for the City of Brass situation to work... but I've never had that happen in play, so I don't want to start piling even more hypotheticals into the thread. So instead I'll talk about an example from actual play in a game I GMed.
The Noble character is a one-eyed Wizard Diviner named Braeda. She and her characters found themselves in a hostile city, where they didn't appear to have any allies. The gates were closed by the High Preist that ruled the city. This was because of some shenanigans the characters had gotten up to. They were spent from a battle, with little left in the tank.
Braeda's player asked me if there are any local nobles. I said yes, despite the High Priest having assumed power some time ago, he kept many of the nobles under his thumb. They made their way to the estate of one of the minor nobles in the city. Braeda approached the gate and demanded to speak to the lord. The player mentioned the background ability.
I said that the guards at the gate weren't inclined to listen... but I wanted to honor the ability. So I said "What does Braeda do to convince them to let her and her friends in?"
The player gave it some thought and then his eyes lit up. He said she raised her right hand to cover her empty eye socket, and that the stylized eye tattoo on the back of her hand flared with light (a cantrip) and said that she was a seer and their lord would want to hear what she had seen. That got them the audience, and was a really cool moment of play.
We worked together and found a way that it worked.
Crazy.