He just had no conception of all the fun technologies that would later come along in a digitized, microprocessor-rich world of the future. Reading 1984 today, you want to laught at the simplistic and almost benign weakness of telescreens for surveillance.
Were Orwell to have been deeply informed about the surviellance mechanisms of the future, he'd likely be both surprised into horror at their innovative intrusions, and completely unsurprised that such a vast percentage of the UK's (and world's) population completely accepts them with hardly a sigh.
The last part wits the nail on the head. Orwell envisioned a future where everyone was forced to have a telescreen watching them at all times. He never for a second dreamed of a future where people would buy a telescreen for the most trifling convenience of going "alexa, is it going to rain today".
This is actually why I always considered Brave New World to be much closer in predicting the future, at least in spirit if not in hard details. Let people access personal distractions, conveniences and pleasures on your road to total surveillance, and attempts at social control, and you can apply them with very little need to ever enforce miseries like those of "1984"
Were Orwell to have been deeply informed about the surviellance mechanisms of the future, he'd likely be both surprised into horror at their innovative intrusions, and completely unsurprised that such a vast percentage of the UK's (and world's) population completely accepts them with hardly a sigh.