https://arstechnica.com/science/2020/12/google-develops-an-ai-that-can-learn-both-chess-and-pac-man/
Now, call me cynical but whenever I see AI try to play Chess or something as 'simple' as Pac-Man a part of me wonders how much AI is involved versus classic problem-solving. Lets think about it this way and use both games.
Chess - Finite position/vector-based game. Only so many squares, only so many moves. Only so many permutations allowing a machine to see to what we may consider infinity till the next move is played. Realistically the only time the AI might kick in is if it learns the other player and then tries to adapt its game but even then the only real move that can trip it properly is the first move. So is it really AI? Not really but lets call it AI because that's cool and in-line with how tech is hyped. IBMs big show and its failure when a human beat it wasn't AI it was just poor problem solving and non-adaptability because lets face it if the AI was really present no human would have been able to touch it, period.
Pac-Man - You'd imagine a game with the limitations of space like Pac-Man would be just like Chess then you realize that the ghosts have finite moves they can execute to achieve goals and more importantly they are non-adaptive so really this is once again problem-solving but with a slight twist. Your problem solving using four moving points to determine the best approach. So is it really AI once again? No. When does it become AI? When the ghosts stop becoming predictable and also use AI to beat the AI that is running Pac-Man. Then lets add that RAND (random number generator) so famously used in the 8-bit era to create the illusion that the patterns you were seeing were truly random. They really aren't, so once the AI pattern matches the seed generator it can go forever without flinching because the only thing the game has to ramp difficulty at that point isn't the ghosts its the speed of the game and with another machine playing on the other side that is never going to be a problem ever. Might be fun to watch though.
In the end I think we generously throw this word AI around at things that aren't true AI. Adaptation is a key-factor yes but so is the process of elimination to determine a play-style that best mimics something that has the smarts to play the game. I also think games are the worst way to describe AI because they are finite in the way they can be played with some exceptions of course. Some of the best forms of AI are in language understanding and cultural adaptation with assimilation.