Nvidia's current service (in beta) does really well. Google's project stream demo went really well for many people. But obviously, one's experience will be contingent upon internet providers, ultimately.

So... Stadia, along with all other current and future streaming services, are going to really suck for a lot of people.

But... they are going to be really amazing for a lot of people too.

Best-case latency should be as low or lower than the latency many play with on their consoles.

Doesn't matter who has tried it or whether it's feasible, speed of light or physics are not reasons this won't work if a company is willing to put machines every couple hundred miles.