The suspicion that statements like this inspire is because unfortunately there are DMs out there who aren't acting in good faith, just as there are players who aren't acting in good faith. In the early days I think DMs had to do a lot of crowd control of the latter, and the default of "if in doubt say no" came from a combination of response to ludicrous requests and adversarial DMing.
One thing I learned from some players was that if I don't say no authoritatively and frequently, they'll behave like rampaging psychopaths (their characters will too). Part of it is about in-game considerations, but part of it is also establishing who's in charge. It's very important that the players understand that.
I'm a lot more choosey about who I play with nowadays, and see very little crowd control.
So am I, and as a consequence there's a lot more concordance between mine and my players' opinions and a lot fewer no answers. That's a luxury, though.
The more opaque the DM's rulings are, the more hidden backstory locks the game down , the harder it is for players to discern what plans are viable and what aren't. I've seen situations where the lack of feedback from the DM renders player decisions essentially random, creating immense frustration. This can cause some players seeking entertainment out of the game in other ways, and acting out, leading to a vicious spiral of frustrated deprotagonised players and an angry frustrated DM.
Sure, but hidden backstory is also essential. If the players don't get the sense that there's a real world out there somewhere, if they get the sense that they're being spoon-fed a specific scenario as opposed to participating in a dynamic living world, they're likely to get bored and quit.
This game is played in the imagination. I think it's very important that there are parts of the game that are not explicitly stated, yet which produce objective consequences. Indeed, I sometimes write down a few themes or have some in-world phenomena in mind before I campaign which I know are important but which I have no intention of disclosing whatsoever. Typically, they'll find out after the game.
It is a real issue when the players become frustrated by a sense of irrelevance, but in my experience the solution to that is simply trust. Sometimes you should feel that way, as most heroes do.
And again, this is an idea that I think is very strongly rooted specifically in fantasy fiction. Every episode of Game of Thrones I watch hammers into your head how the world is bigger than what's oncreen, and things matter that happen offscreen. There's an enormous amount of hidden backstory. And of course Tolkien was the king of hidden backstory.
Roleplaying is a different medium, but I think the idea of hidden backstory translates very well. Have a few details that the players don't know, and then they start thinking, and fleshing out innumerable other aspects of the world in their own heads. The power of imagination is much more important than the power of game rules.
My solution to such problems is to try and nip them in the bud. If the players concoct a plan that isn't viable, let them know that before they waste the whole session on it, and try and impart at least some of the information why that is the case.
In general, that's probably wise. One of the benefits of being a DM is you know an innumerable number of things the players don't. In world, most D&D characters are exceptional and intelligent. There's every reason to believe that they would intuitively know a lot of useful things. I spend a lot of time trying to impart that wisdom to players without spoon-feeding them.
There's a fairly interesting bit in the DMGII about whether if a player says he opens a door and walks into a room, and (unbeknownst to him) there is a pit behind the door, whether the character should walk into the pit and fall, because the player said so, or if the DM should intervene in the name of having the character behave rationally because the player said something unknowingly but the character is not that dumb. I fall firmly on the side of intervention, of telling the players what their characters would know and letting them make the most informed and in-character decisions possible.
Also, most players nowadays have more experience of various RPGs and are more open to making the game more of a collaborative process than an adversarial one. The players aren't the enemy and treating them like the enemy isn't appropriate in most games IMO.
To me, adversarial DMing is the old school. I haven't seen it done in a while and I never saw it done particularly well (and I'm very heavily collaborative), but I imagine there's some great experiences to be had with that mentality.
Fortunately, I didn't have to refute this because Ahn already did. But this right here strikes me as the bad faith in this discussion. He never said nothing the players attempt can ever succeed. He closed off one thing as far as I can tell - using diplomacy to get an appointment with the king. And here you go blowing it far beyond what he ever said to try to make your points.
There's probably another jargon barrier here, but in this scenario, the outcome of the game is not being determined, merely the outcome of one fairly trivial action. Besides being an entirely reasonable phenomenon, the refusal of royal servants to talk to strangers does not subvert the player's fundamental goals unless they signed up to play a game where the only goal is talking to the king.