Jeff mentioned that it is not that easy to find out if a given game is available with a "gaming subscription". I had the same issue and build this simple little thing to keep track of it:
Maybe you'll find it useful. One thing I found for example was that Playstation Now has a LOT of games and they seem to add quite a lot of them as well. Xbox game pass is still better for me though because they tend to have much newer games than Playstation Now and not just counting the Xbox Game Studios first party games.
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