I thought of OnLive, Shadow, and Geforce Now.

The only one of those I'd used was Geforce Now, and found it very similar to Stadia wrt latency. Stadia had a much nicer interface, though.

PlayStation Now already existed for years as well.

Which they got through their acquisition of Gaikai (considered a competitor of OnLive).

The discussion was about innovative products. An already explored idea, but executed properly, only counts as innovative if Apple does it. And even then, it only ran for a couple years, so even if we want to give points for taking an idea and making it work, they don’t pass there either.