a bit of an odd situation, the game actually wasn't a full Stadia exclusive. hitting the standard PS4 Xbox One and PC set.
but the developer, Typhoon Studios, was bought by Google a month before the game launched. with plans for any further installments being locked to the platform.
needless to say, they were shuttered fairly quickly (as in, literally the same day the game was added to Stadia.) as Google gradually unwound the service.
the former staff there reformed under a new studio, Raccoon Logic, and Google decided to just give them the IP back.
so now they're working with the original publisher for the game to re-release it on PS5/Xbox Series, it also sounds like the cancelled sequel they were making at Google has been revived in some form. presumably launching a few years from now.