I think those that are struggling with the "Story Engine" concept are stuck in a world of linear storytelling and binary experiences. We are not talking about things that you line up in order to "try," like waving a wand to make something in a window move. We are instead talking about a living breathing world around you that all of a sudden you have a place in. Off the top of my head here a few random interactions that may occur:
A First Order Patrol stops your group and asks for your documents: They know with a quick scan whether you have been engaging in activities that support their regime or have been participating in activities as a resistance sympathizer and act accordingly.
A shop keeper in a bazaar knows from 20 feet away that you are carrying a kyber crystal and engages you about the force and its power.
A stranger slides in line behind you and passes you an urgent message trying to recruit you as a resistance operative.
The barkeep at the cantina refuses to serve you because earlier that day shot and killed a friend of his in a battle. You deny it, and he shows you a picture of some creature you did indeed shoot on a ride, but serves you anyways because he needs the credit.
This a world with a hundred cast members who each have "the story engine" whispering in their ear or flashing on the screen in front of them sharing pertinent intel and backstory on anyone they choose to engage. This is a world with hundreds or perhaps thousands of interactive elements most of which the guest is completely unaware of. The "Story Engine" knows which button you hit in the interactive line. It knows you lingered over this display or that piece of merchandise. It knows you bought a lightsaber or Kyber crystal, or went through Jedi training or traded something with that jawa or had an unsavory encounter in the cantina. It has been watching your every move. IT knows if you can handle a freighter or a blaster, and what you like to drink.
This is a world where every droid, every screen, every cast member, every door, every light, every prop, every ride element, and every bit of scenery is like the sword in the stone, just waiting for that person who can pull it free, only these props don't just have the binary choice to stay secure or come free, they have 4 or 6 or 8 or 10 different ways to respond and engage depending on the individual. Each one of these is being continually controlled by the "Story Engine" to guide every guest through a unique experience they create together in real time.
This is not a world where you line up to have the droid beep at you. This is a world where you are walking around minding your own business and the droid comes after you, or runs away from you, or shoots at you, or delivers a secret message to you, or welcomes you, or scoffs at you, or tells you a joke, or offers to hide you, or starts shouting for the first order to come and arrest you, or, in most cases, is completely oblivious to you. You don't have control over it, you don't line up to have it happen, It just happens.
90% of the guests or groups are completely ignored by any given element. Out of those engaged, 99% are engaged simply and benignly. That leaves about 1 in every thousand (or perhaps 2000-5000) with a large meaningful interaction with a given element. That means this one droid would engage in a large and meaningful way, once every 20 minutes to hour (assuming attendance numbers that rival MK). These engagements are not timed, they are not even random, they occur when a certain (unknown to the guest) set of requirements are fulfilled by a guest or group as determined by the "Story Engine."
In a world like this, every guest would have a dozen or two dozen minor, but personalized interactions with the world. Maybe half of them would have some larger noteworthy, but not magical encounter. Maybe 10% would experience something magical and memorable. 1% would have the type of experience they never forget, that they tell their friends and family about for the rest of their lives.
The more you engage with a world like this, the more likely that something memorable would happen, but that doesn't mean that even the most passive guest or humble visitors couldn't find themselves involved in something amazing. After all, even a slave boy and a simple moisture farmers from Tatooine had adventures and destinies that shook and shaped the entire galaxy.