Before AlphaGo's achievement, it was still expected to occur, but the expectation was in about 20 years with much more developed tech. The shock and surprise wa

Before AlphaGo's achievement, it was still expected to occur, but the expectation was in about 20 years with much more developed tech. The shock and surprise was that using larger scale of combinations of current tech could achieve the feat. The qualitative change in worldview is that 'dumb' machines can do intelligent things. AlphaZero was a tour-de-force of how dumbness can excel. In hindsight we can say that these things happening in our lifetime with tech of the day isn't surprising, but if following closely as-it-happened, it was a big surprise to everyone including the AlphaGo team. I don't think anyone knew if there was any limit where efficiency/effectiveness of the systems being built would top out in the complexity it could tackle.