This.
It's not just that the XB1 version is an over sharpened mess, people who are complaining about the 'blurry' PS4 IQ are noticing the FXAA. It's such a terrible AA solution in terms of what it does to IQ, it's cheap though.
I've used FXAA, in its various incarnations, and it's never been this blurry. But I actually hope you're right, and future PS4 games forego this particular implementation of FXAA, and go with something like SMAA or even MLAA instead--less blur, generally speaking. I was just worried that this slight blur might be due to the PS4's scaler--something not as easily remedied as merely tweaking AA settings.
Fwiw, it seems FXAA on low settings doesn't introduce any noticeable amount of blur (to my eyes).