I don't think Google really has a game plan (no pun intended). They never gave Stadia the dev and marketing resources it needed so it just died on the vine. Their "pivot" is more like a surrender, I think, an act of desperation where they hope other companies will pay them for their tech that never really took off with consumers.
Thing is, porting to Stadia is so much work vs flicking a switch in Steam to publish to GeForce Now. And Stadia can't cross play or cross save with anything else by default, making it a very lonely ecosystem.
That is why they are now writing a Windows emulation layer for Stadia, which I think won't convince anyone that isn't yet bought into their Stadia sales pitch. See last week Stadia sessions for developers.
Thing is, porting to Stadia is so much work vs flicking a switch in Steam to publish to GeForce Now. And Stadia can't cross play or cross save with anything else by default, making it a very lonely ecosystem.