In the trenches, so to speak, AI was heralded as the next coming of jesus superior advanced algorithms...however it kinda turned out to be a bunch of bunk so far because all you end up with is an over-optimized multivariate algorithm that is no good at doing anything other than what its training test data suite encompassed. (speaking from experience in the realm of using/developing/advancing AI algorithms for finance modeling)
In a number of fields, AI has done very well for itself (depending on ones EXACT definition of AI).
For example, Chess computers in the late 1970s, early 1980s were easy to beat, by even fairly low end human chess players.
These days, even the Human world Chess champion, would have extreme difficulty beating a very strong program, on a powerful enough computer.
The game of Draughts (I think it is called Checkers in US), has been fully solved, and the end game result effectively known/proven a few years ago, now.
I think what happens with many AI systems, is that they show amazing/great/good results in the early stages of development, which makes the project go well, and get more support.
i.e. Low hanging fruit.
But later on, things tend to get massively (exponentially) harder, and ever increasing amounts of AI team efforts and/or computing time, produce little real improvement to the AI things abilities.
i.e. High/difficult hanging fruit.
Going back to the Chess program, AI example. One that is capable of beating the world chess (human) champion.
Although technically speaking, it IS AI. Really, it is just a (mathematical like) program, often written by someone who is a very good chess player. With a somewhat "brute-force" type of computing algorithm, rather than something which is made out of "Pure" AI elements, such as neural networks.
i.e. It just goings though a huge number of possible moves, scores them, and chooses the one with the best score.
So it is really showing how fast and powerful, todays computers have become, rather than "real" AI.
E.g. Plug a microphone into the chess software, and say "hello" to it, will probably NOT get an answer of "Hi, I'm fed up with playing Chess, can I now post on ATOT, with a thread about "Why do people post stuff on forums, when they have got better things to do, such as play me chess games ?"