Netflix is a good comparison because google will need to secure rights for AAA games, and some games don't appear in all platforms.

Fortunately, a user can install Steam/GOG/Origin whatever and just pay for a single game, unlike video streaming platforms.

In terms of pricing, 9$99 for 4K/60Hz games is 120$/y; if you buy two AAA games (around 59$) it's already the same price, so in the end the appeal is NOT having a beefy computer to play whatever game you'd like. My guess is that hardcore games will have their own PCs, console gamers prefer TVs but the "casual" gamer may be attracted depending on the catalog of games.

edit: it seems you have to buy most of the games too? So google is basically renting a gaming PC with a higher latency.