I think I am making a similar claim in relation not to two particular systems, but two reasonably broad but also recognisable play priorities:
Your claim is incorrect.
players exercising agency over the content of the shared fiction by way of action resolution
players learning what setting ideas and elements the GM has come up with, and enjoying the experience of learning them by way of second-person narration
I think it's pretty hard for the same episode of RPGing to serve both those priorities.
While it might be difficult or impossible to serve both of those priorities within the same action, it's absolutely possible to serve them both within the same episode, adventure, campaign, etc. I do it in every single game I run.
Your inability to accept this is clearly why you have such a hard time understanding dissenting responses in this thread.
For example: This weekend I'll be running a one-shot for a friend and his two sons. I've decided that:
- I want to go with a gothic horror theme.
- Werewolves and vampires are played out for me, so I want the primary antagonist to be a flesh golem.
- The flesh golem didn't create itself, so I'll include a wizard/mad scientist character that created the golem.
- I don't want the two to be allies, so I'm deciding the wizard botched the amulet that would control the golem; the golem has run amok and it resents its creator.
- I also like including undead in my adventures; so the wizard's harvesting activity in the town's cemeteries gives me a natural way to involve undead, and they can provide a way for his shenanigans to get noticed.
- That means there's a town, so I should come up with a few details. I'll name the town Crow's Landing (a play on "Ravenloft", with which my players are unfamiliar).
- "Crow's Landing" reminds me of "crow's nest", a nautical term, so I decide the town will be a port. That means the sewers beneath the town probably connect with the ocean via some sea caves.
- There's probably a lighthouse, as well. Availability of corpses means they don't bury their dead at sea, so they probably don't view the sea god(dess) as benevolent. That also means the cemeteries are either uphill and landward from the town or the townsfolk are willing to struggle with waterlogged earth to get the bodies into the ground.
- The second option seems more thematic and interesting, so I'll go with that. So, maybe the wizard was creating the golem to expedite digging up corpses, since that's clearly hard work.
- There will be an inn, the Sea Dog's Roost; a tavern, Black Bart's; a temple to the cult of sea-god(dess) worshippers, probably in secret; and a church that maintains the lighthouse, since it represents a bastion against the dangerous sea.
- Since the lighthouse is a religious, protective structure, I'll place the cemeteries in its shadow. That means the lighthouse can only be accessed by passing through the cemeteries.
- And, now I have my hook. The lighthouse requires some kind of maintenance or resupply, but the wizard's activities have the townsfolk/clergy spooked. Someone has to brave the cemeteries to reach the lighthouse.
- Also, I'll add the threat of an approaching storm. This is a one-shot, so I want to instill a sense of urgency from the get-go.