I agree with Schreier that Google now has a big enough investment in the industry that it's not going to leave the industry suddenly.
However, I'm not sure that necessarily means that they will have to stick with Stadia. Their game development efforts could potentially be directed towards other platforms.
I think it actually might exist, although probably right now it's a latent market. There's lots of people who have been introduced to games in general in the past ten years through mobile games, and statistically there must be some percentage of them who are ready to expand their gaming tastes to other types of games.What Google seem to be banking on is that there's an untapped market who are just clamouring to play Final Fantasy XV but haven't found the right platform yet. Does that audience actually exist?
Even if that market exists, though, it won't automatically buy into a new platform even if that platform is super convenient for them - it would be a market that needed to be carefully nurtured with the right product, and there's no indication that Stadia is that product.