There are two issues with it. One is specular highlights. He doesn't show this in the comparison, but you would see it flickering in the two marked areas in full screen at around
14:36-14:40.
EDIT: It's actually even more visible a few seconds before around
14:34
The other is slightly more distant detail with TSR in stills. This is simply how PSSR works in general. It's softer. This is simply due to slightly different levels of sharpening between TSR and PSSR.
Overall, neither issues are worse than the very obvious noisiness of TSR, which is in the same comparison footage but he somehow glosses over. There is so much visible flickering with TSR that's far more subtle with PSSR in that comparison.
And who cares about stills, right? So imo, PSSR is better as per the shown footage. Nothing dramatic. Not even by a good margin. I'm just glad it didn't shit the bed like Silent Hill 2.