It's not hard to realise, Scrap. Why need a book to get the conclusion that people are fucking you over etc? It's pretty obvious if you used common sense and looked around you. Orwell wrote 1984 from observing Stalin's rule, various observations of other dictators along with emerging technologies concerning video conferencing etc for example.
Because you may be getting fucked over in a manner that you don't recognize. By looking at totalitarianism from another perspective, you may see things that you didn't see before.
For example, the constant erasing and re-writing of history. Most people aren't aware that it's being done, but it's a central theme of 1984. History is thrown down a "memory hole" that incinerates it. That brings up another brain-washing method, naming things the opposite of what they are.
...and the list goes on and on.