I think the discussion is getting off track a bit but.... If I'm following the discussion right this might be the first time I've agreed with @Chaosmancer to such a significant degree. The responsibility for making a coherent world does not rest solely on he shoulders of the gm unless the GM is ignoring all official/example settings for the system & making something whole cloth from scratch. The publisher has a responsibility to ensure the base setting(s) they provide some reasonable level of cohesiveness & consistency rather than an endless march of isolated plot armor bolted all over a map simply because a failure to do so makes the job of the GM & players trying to operate within that world.Nope. The world is mine. They write source material that I pick and choose from to save myself some work. Where there are contradictory sources I choose whatever I like best.
Other DMs can do what they please. It has no bearing on what I do, what I do has no bearing on what they do.
It's never happened.
Yes.
No, do not put words in my mouth. I am not the manager, I am the dictator. The only way the players can affect the world is through the actions of their characters.
That world does not need to be modeled down to the finest detail; but if the setting is known for having a gigantic port city with massive political clout like waterdeep I should be able to point at the nation it exists in/rules over, the borders of that nation, & one or two other nations it trades with if said nation is not the sole power in some dystopian hellscape world. If a setting is known for particular race like orcs being powerful & frightening raiders that are a threat to all of civilization I should be able to point at a reason that doesn't involve plot armor like "because the gods" that explains why those raiders have not been wiped out by an alliance of the civilized world, walled out great wall style, or conquered the civilized world to unfurl a new dark age of collapsing civilization & "because the gods" is not it. If a setting is well known for having bonkers over the top magic items all over I should be able to point at a few ways it gets used for civilization that don't involve wandering mercenaries & mass murderers known as "adventurers" or there should be some explanation for why the price of magic is too awful for such things.
if it can't meet a bar like that the setting does the gm & players a disservice regardless of if they want coherent consistency because the gm who doesn't care about those things can continue to not care while ignoring them