Relatedly: before I read 1984 I thought I wouldn't get much out of it. I kinda thought "yeah I'm sure this was incredibly eye-opening at the time it was written, but these ideas are pretty mainstream in the cultural zeitgeist now, there's not much that's going to be illuminating in it to me".
But I was so wrong; Orwell does a phenomenal job of painting an incredibly vivid and unsettling picture of what that society would look like. The "bullet points" that came from general cultural awareness don't come close to the experience the book conveys.
The thing I remember most was how "stuck" everything felt. Like it really sank into you that the 1984 society had reached some tipping point of shutting down conversation that it didn't feel like it was possible to recover. All parts of the system all throughout the stack were keeping everything in check, and you got the sense that it wouldn't be possible for people to break out of it even if a lot of the people in power wanted to.
But the main point is that I'm not Orwell, so nothing I write about what I took from the book could substitute for hearing it from Orwell directly.