Files can hide lots of stuff. Just think about how much information is on a typical computer, or even a phone these days. It could take years to go through all of that and find something that is of interest.
It doesn't even have to be digital files. Imagine heroes breaking into an office and finding a few filing cabinets full of papers. They're looking for... maybe some evidence that the office owner is doing something dodgy. I hope they have a few hours, at least. Of course the security guards won't give them a few hours. Or even the sunrise and people arriving for work the next day, when it comes down to it.
The solution of course is to steal the files and go through them at your leisure. You might even be able to hack a computer and copy the files remotely. But how are you going to steal three bulky filing cabinets, weighing maybe 100 kg or more?
Commentary by Keybounce (who has not seen the movie)
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Commentary by memnarch (who has not seen the movie)
An embarrassing experiment outcome, especially if it's part of a VIP's pet project, could definitely result in a grand cover-up to protect the VIP's image. Vanishing the project (and anyone that talks about it) is definitely something I can see the Empire doing. Might be a bit too "on the nose" for a family movie though. So maybe beyond a vague reference to Rogue One for the fans (which I'm also waiting to see after the Episode IX comic finish), the new hyperdrive modulator source isn't explained.
Aw, Death doesn't really dislike anyone, except people who are cruel to cats; Yanni probably just has an extremely high Luck score. And has been extremely unpredictable so far, so nobody could kill him off except by Yanni going to them. Which didn't even stick last time! Hmmm. Killing wasn't actually the point there which could mean no one has actually tried hard enough. The rathtars came pretty close though!
Finn: If the Empire had this hyperspace technology 40 years ago, why have we never heard about it? How come nobody uses it?
Rey: The ship that was testing it crashed on Tatooine. Presumably something bad happened, and they abandoned it.
Finn: How did you learn about it?
Rey: Resistance data analysts were going through old Peace Moon plans recovered from the Empire.
Rey: They found a folder full of PowerPoint files by the original designer.
Rey: Some of them mentioned another project—an experimental hyperdrive—and suggested a test above Tatooine.
Finn: And you said earlier that an agent connected it to the crash site. Hmm.
BB-8: I knew using that modulator was risky!
Yanni: We’re still alive, aren’t we?
Chewbacca: At this point in our careers, I’m beginning to think that Death dislikes you as much as everyone else does.