From what Quanatic Dream has said, the PS4 version of the game that is coming in July is NOT the 2015 Fahrenheit: Indigo Prophecy Remaster. The announcement Tweet left of the "Remaster" moniker off and that now seems intentional
The PC, Mac, Linux and Android 'remastered' version of Indigo Prophecy wasreleased by Aspyr Media, Inc. But, when Quantic was specifically asked if this PS4 version was the same version,they said ist wasn't. The announcement Tweet for the PS4 version thanked SIEA, which is Sony Interactive Entertainment America. Not sure why the switch form Aspyr Media to Sony. But it could have been a timing issue or personnel issue for the porting. Sony has 'tiger teams' for coding from whatewe know, so maybe the switch needed to be done quickly or they just went from PS2 code to create the PS4 versions. From the point of view of 'Occam's razor', the easiest explanation is often more likely than any twisted logic conspiracy theory.
Either way, whatever the code base; I look forward to getting I.P. for only $15 in July!