I don't personally think so, no. Shadow Fall was disappointing, I think everyone can agree on that, but the larger Killzone history across PSP / PS3 still ranks Guerilla Games just behind Naughty Dog as the second most technically impressive Sony exclusive studio. The Killzone games on both PS3 and PS4 are technical showpieces; Shadow Fall is a boring game with no heart, but it's still a graphical powerhouse. Beyond that, the Killzone games on PS3 had a look/feel that was completely unique. Sony unfortunately abused/maligned that uniqueness with their silly "Halo Killer" marketing attempts, but it doesn't change the fact that Killzone did it's own thing in the COD/Halo market and still managed to do it very well.
Shadow Fall, on the other hand, seems like a pretty obvious case of Sony pushing too hard for a launch title and Guerilla being unable to complete much more than the engine/shell of a game with a thin/disconnected layer of story around it. The fact that Guerilla pushed directly into Horizon after SF tells me that it's very likely they had little interest in making another Killzone game and probably only did so under pressure from Sony. My personal read on it is that Horizon is the real PS4 passion project for the studio, and based on what they did with Killzone 2 in a similar situation (for PS3) along with the reported enthusiasm of almost all of the games critics/journalists I've read/heard I'm still very excited and optimistic about it.