The two books differ in how they describe the source of the dystopia. It's been a while so please excuse any inaccuracies - in 1984 the world is controlled by authoritarian governments through fear, misinformation, and endless distractions, whereas in Brave New World the world is controlled by an authoritarian government through mind-numbing pleasure and shallow entertainment. The governments in these books both rely on citizens being reduced to their lowest common denominator. I think people during the cold war could most easily imagine, and thus be most afraid of, a world that resembled 1984. The book I mentioned in the beginning of this post argues the view that we should have actually been more worried about a world more closely resembling Brave New World.
Today we are constantly fed a mind-numbing amount (mis)information that we also simultaneously look for because it makes us feel better. Unfortunately, this media barrage also robs us of our attention and ability to critically think about important issues affecting our society. If anyone is interested in reading a book written before the age of social media (published 1985) and exploring these ideas, I highly recommend this one.