Stadia was
not ahead of its time. It was a latecomer to a growing field that Google dipped its feet into, but never fully committed to. I'm pointing this out not to be pedantic, but to illustrate just how thoroughly Google dropped the ball on it.
In 2010 OnLive was launched to the public, creating the first version of a public Stadia-like service. It worked the same way; you opened a browser or an app and you could play a game that you bought on it (I think back then it was a subscription model? can't remember)
Around the same time, Gaikai and Sony partnered up to create the predecessor to Playstation Now streaming.
Then Nvidia entered the game in 2012, right around the time they started adding hardware-accelerated video encoding to their GPUs, launching Nvidia Grid with some partners. By 2017, Grid evolved into GeForce Now and could play the user's entire Steam library (unlike today, back then ALL games were available, not just ones opted-into by the publisher).
Stadia didn't come around until 2019, nearly a decade after OnLive. Google being Google, they didn't want to do what Nvidia did (make existing games playable), but instead created their own architecture that was easier to launch and easier to use, but required users to re-purchase existing titles, usually without cross-saves and cross-plays. (Edit: It also required devs to spend time and money porting the game to Stadia's platform, vs a one-click opt-in for GeForce Now). So it sat in its own little bubble, away from the entire rest of the PC ecosystem (which was Steam and/or Games for Windows back then). It also had inferior graphics compared to Nvidia's cards (notably lacking raytracing, ultrawide, etc.) and Google flat-out lied about its capabilities (like Orcs Must Die 3 games being made a Stadia exclusive at launch because "only the cloud" could run it smoothly, except it came out on Steam a year later and was just fine).
They did some minimal barebones marketing targeting casuals. Fast forward a few years and they just completely abandoned it, while GeForce Now continues to grow, gaining EA, Ubi, and now Activision Blizzard games as official partners. Amazon has Luna, Microsoft has xCloud (or whatever it's called now), Playstation has PSNow (or whatever it's called now), Shadow, Boosteroid, AirGPU etc. are all alive.
Google didn't invent game streaming. They didn't perfect it. They launched a slightly more polished experience that was significantly more expensive, had terrible sales compared to Steam and its 3rd-party resellers, and and gave up on it in its adolescence. There was nothing "ahead of its time" about it, it was just another could-have-been that Google toyed with and never seriously invested into.
https://en.wikipedia.org/wiki/Cloud_gaming#History