Gamepass poses no threat to Sony at the moment, and i dont think it will do in the long run.
Because it's an experimental businnes model in the gaming area, to really work it needs several hundred of millions of active subscriptions. Why an AAA publisher would want to get a small revenue share from its titles while can sell them for $70-$80 each?
Also, videogames are something very different from films and tv series, they need time to be completed.
Netflix can safely remove any film without damaging the costumers; films are tipically just 1h to 3h long, experienced in a single shot.
A videogame is a different experience, it may last for hundered of hours... what if a game you are playing is removed from the Gamepass without any notice?