Stadia was killed by Google. Cloud gaming is still alive and well in services like Microsoft Game Pass. Google put cloud gaming in the center, selling the idea of cloud gaming as a revolutionary platform. Microsoft instead put cloud gaming in the right place: as an added feature for a great service.
Cloud gaming is a very interesting features. I ask myself when Valve will also adopt it. I have a lot of friends with MacOS willing to play the same games with other friends with PCs. Cloud gaming would be a great add to Steam.
Cloud gaming is not the future of videogames, thou. Until now, in fact, there is not a single scenario in which Cloud Gaming offers something better than classic Console/PC gaming. Usually performances are better on console. Also, people who cannot afford best devices usually has access to worst Internet connections too. So that the market for pure cloud gaming is very small.
Cloud gaming is a feature and not a platform.