A leaked slide from Sony’s internal presentation has revealed the Steam sales for all of its ports that have hit PC over the past couple of years. Do note, though, that this slide is from February 2023. As such, it does not have any sales numbers for The Last of Us Part I.
Demon’s Souls is owned by PlayStation. They made Dark Souls as a series because Demon’s Souls wasn’t something they owned. I believe the dispute goes back that far.