There are two different definitions what AI is. The first one was created by the AI community itself. In most cases it is about robots and other sort of advanced algorithms which can solve problems. Typical example would be a self driving car, a chess AI or a machine translation software.
The other definition about AI is what the public thinks about the topic. In most cases the public likes to know if AI can replace human workers. It is important to know that there is a gap between both definitions. It is possible to create AI according to the first definition but fail at the same time according to the second definition. Let me give an example.
It is possible to program a chess AI which will defeat any human player. There are some Open Source projects available which are well documented. The assumption would be that with the existance of such algorithm normal matches between human players are no longe needed because all the games can be played by software much better. The surprising observation is, that since the 2000s more matches between humans are made before. In spite of the existence of powerful chess AI there is a demand for human opponents.
The same situation is available for a hospital robot. Today's hospital robots are highly advanced. They are equipped with cameras and natural language processing algorithm. At the same time it is not possible to replace human service employees with these robots. The demand for human labor in this sector has increased. The prediction is that after the invention of improved future AI systems nothing will change for the public. That means AI will never replace human chess players and won't replace human hospital employees.
All these promises which are going in this direction are either illusion or simply science fiction fairy tales. From a technical perspective it is possible to build intelligent robots but these robots are different from humans and they are not what is needed by the society.
Let us describe the situaton for chess playing AI in detail because the subject is easier to understand. What is the purpose of the “GNU Chess” engine if it can't replace human players? In case o ELO score the gnu chess program is great. It is a very powerful chess AI which never makes a mistake and contains of advanced algorithms. Most chess players are not interested in playing a game against this engine itself but what the human chess experts are doing is to research the subject of computer chess. They want to know how gnu chess was programmed which bugs are in the code and how to improve it. So it is a self referential task. The engine is improved with the reason that the new version o gnuchess is interesting for a new generation of AI researchers.
The subject of AI is a large and very interesting topics. There are many subdomains available which have a scientific background. The only thing what AI can't do is to provide a value apart from AI itself. No matter how advanced a software or a robot was it won't affect normal life. This rule is not fixed and most AI researchers won't confirm it. It is only on observation which is made for AI projects from the past. The paradox situation is that from a technical standpoint AI has made big improvements over the decades At the same time it is remaining unchanged in terms of the ability to start a revolution.
In any decades the people were afraid of the upcoming robot revolution. They are in fear that their jobs are replaced by automation. But only 10 years later the former utopian promise gets forgotten and not a single robot was installed at the assembly line. The problem is not located in a certain sort of computer or algorithm but it has to do with AI in general.