I think there is a chance that Google may still release a Google Android gaming device since Android has better offline support, and games are playable on slower internet connections compared to Stadia which needs a fast and stable internet connection to work.
Well, I doubt they would want to start any more gaming projects for the moment. They'll want to see how Stadia goes and whether it is worth it to continue on in the gaming industry.
I feel there are also enough Google Android game consoles like the Nvidia Shield TV, and Smart Android TVs where Google and Android gamers may not feel the need for Google to release an official game console for Android.
A lot of Google Chromebooks from Google, Asus, Acer, HP, Dell, etc now have touchscreens, and Google Android game and app support, so there maybe no need for Google Android consoles when Chromebooks come with more storage space like 1TB, and become cheaper to buy like $100 to $300.