Because people are assholes.
The current generation of gaming (on consoles) conditions you to low resolutions, screen tearing, aliasing, blurry textures and low framerates and you stop noticing after a while. It's normal, it happens to me too. Then you play a 1080p60 game on PC (or even consoles, wasn't Ninja Gaiden Sigma 2 a 1080p60 title? I remember it being awesome on PS3 somehow) and you're like "I CAN SEE AND REACT TO EVERYTHING. EVERYTHING!".
That being said, I am very picky about this sort of thing. 720p I will tolerate disapprovingly, depending on how the game handles it. I originally owned DMC4 on PS3 and enjoyed every minute of it. but 30 fps? lolno.
I remember when console games didn't even try on the graphics front and instead focused on gameplay. Seriously, there's nothing wrong about a game that has average special effects or polygons, or even textures. But image blurriness and low framerate actively detracts from the actual GAMEPLAY!
Thus, a 6/10 for the console version of DmC is in order. It's slow, it's blurry, it's choppy and it responds late to inputs. The core game brings it avobe mediocrity, but there's only so much you can do about a game that's punishing to play for the wrong reasons.