IMO I think Silent Hill, and Ueda's games too, are sort of a seller in that Sony makes games for the sake of making great games, especially as art, even if they are a lost cause commercially. TV networks have always done this, keeping critic darlings around for 3-5 seasons even tho ratings are middling. Think Six Feet Under, The Wire, Breaking Bad initially (first 2 seasons)
So while yes, each individual entry won't necessarily move a bunch of systems, I think the known fact that Sony releases games that cater to niche audiences helps move systems too idk if that makes sense. Kinda like HBO dramas that aren't going to move subs like Game of Thrones.
Sony games that probably don't move lots of units, but together I think they contribute to move units as it makes PS brand seem to have a wealth of unique games: Concrete Genie, Astro Bot, Last Guardian, Gravity Rush, Medievil, etc.
