What phrase would you use to describe the failure to produce an AGI over the last 50 years? I suspect that 50 years from now we will might be saying "Wow that was hard, we've learnt a lot, specific kinds of problem solving work well, and computers are really fast now but we still don't really know how to go about creating an AGI". In other words the next 50 years might strongly resemble the last 50 from a very high level view.