The Xbox One CPU has almost no advantage over than the one on the PS4. These recent game releases developers have been focusing all their time getting the Xbox One version up to run well and then doing a quick port on the PS4 version. There's no reason the PS4 should be dropping frames like it has been.
It seems like developers are so focused on parity that they try their hardest to get the Xbox One running up to snuff and then by the time the game is set to release, they forgot they haven't put any time in developing the PS4 version.