and? I actually played both.. We know you haven't and I purchased the PS4 Pro version as it wasn't a major difference when I played both.
Softer of course its upscaling a non native image to a a native image.
It happens all the time with say 4 example 900p vs 1080p as 900p looks like a softer 1080p or 1080p looks like a sharper 900p. Nothing major and do you really think a 1800p image upscaled to 4K is going to net significant over a 1440p upscaled to 4K LOL?
I don't need to play both to immediately notice its noticeably softer. I have a 4k TV to see the video on, and even compressed I can tell there is a difference, which would be even more onscreen.
I'm in agreement with DF, its noticeably softer. No big deal.