Typically I'm not a fan of blur filters.
However, the shadows can have too hard of lines, which is why soft shadows exist. I'm not sure how I feel about the ones here.
With blur filters you have to see it in motion. Motion Blur is more resource intensive than not having it at all. Motion blur is obviously going to make things worse when it's not in motion :P.
But despite him arguing to the contrary, you cannot do good comparisons with images on youtube, especially with low resolution shots which those are. The compression can cover up potential benefits that the higher resolution GT6 has. It's entirely possible that the compression covered up the benefits of the things in GT6, while not covering up benefits in GT5.
I'm not defending GT6 for any reason, I don't plan on ever playing it. And based on those two images he showed, I'd agree that the GT5 ones look better, however. It doesn't make it a good analysis.
Essay Pro