Amazon is notorious for posting listings for games that aren't even on a specific platform yet, and just this morning that that very thing happened for Horizon Zero Dawn.
The listing was posted by Amazon France, and it claimed that Guerrilla Games' Horizon Zero Dawn would be coming over to the PC. Funnily enough, the listing also says that Sony is apart of the transition, and not too long ago Kotaku's Jason Schreier said that Sony was looking at bringing Horizon Zero Dawn over to PC. While this could easily be a coincidence, the correlation is still there.
Maybe Sony and Guerrilla Games are currently working on a PC port of Horizon Zero Dawn behind the scenes. It should also be noted that the third anniversary for Horizon Zero Dawn is almost upon us (Feb 28th), so maybe an announcement could come soon? Another fact to take away from this is that Horizon Zero Dawn is built on the Decima Engine, which was given to Hideo Kojima to build Death Stranding and Death Stranding is arriving on PC sometime later this year. So maybe Horizon Zero Dawn will receive the same treatment?