August 2018 - last edited August 2018
Yup, I got the same issue too. It's as if the screenshot is taken at a lower resolution and then resized to match the higher resolution. As my story requires a lot of screenshots, this basically makes the game unplayable for me.
This has happened to me, too. I've compared to a Fraps screenshot and the in-game screenshot has a definite quality loss. I thought this was just me. So glad I'm not the only one. For me, I wouldn't say it's "blurry" per se. More like the anti-aliasing isn't as high quality. I noticed jagged edges in the screenshot compared to my normal gameplay and Fraps screenshot.
I play on a MacBook with mostly low settings, and I've noticed too, especially when taking screenshots in CAS. I'm pretty disappointed. I guess I'll use the full screen command to take pictures until this is resolved. I hope it gets fixed soon!