Now that you ask, I wish I would have written down my predictions at the time (I was 15 in 1980) and could compare. Maybe I should now. I might be still alive in 2050 to realize how wrong I was. Unfortunately, I can’t really tell anymore what I expected back then.
Amongst the things that have already been mentioned :
-No way I would have predicted the fall of the Soviet Union and it splitting apart, even though I do remember reading a book at the time predicting exactly that (“L’empire éclaté”, published in 1978), nor the resulting events (like the war in the Balkans)
-I expected the EU to be more integrated and smaller than it is. I still think we would be better off if it were.
-I didn’t expect that so many dictatorships would become democracies (Asia, South America, Eastern Europe…)
-I wouldn’t have been surprised much by the ubiquity of home computers. I did expect I would play wonderful games on computers later in my life. I must admit that nowaday graphisms are beyond my wildest expectations at the time.
-On the other hand, I wouldn’t have guessed the creation of something like internet.
-I didn’t expect much space exploration. It already was quite obvious at the time that we weren’t going to send anyone to Mars anytime soon. So, I guess my predictions would have been close to the reality (unmanned exploration, rovers…)
-I was very surprised when the first exoplanets were detected. I wouldn’t have thought it would happen in my lifetime.
-Same thing with mapping human DNA : no, not going to happen during the next 30 years or so.
-I would have expected much more striking medical advances.
-Things like GPS and items in your pocket you can use to give a phone call, check a database, take a picture, update your agenda, play a game, look for a restaurant, wake you up in the morning, find your way in an unknown place, and so on… That’s the stuff of SciFi. Not going to happen in my lifetime. If ever. Absolutely no way. Totally excluded. Laughable.
-No flying cars or such things. These were already a joke in the 50s. Nobody has been expecting that during the last 75 years.
-But fusion power should have made much more progresses. My predictions probably would have included fusion power plants by 2014.