Bought Killzone Shadow Fall a few months ago digitally for $5 but can't get into at all. It just feels so outdated compared to other FPS that I have played this generation. Gorgeous looking game though. With that said, I was hoping that Sony would have kept the Cambridge studio open for a new Killzone game but now, im 100% certain that the second team with the guy from Rainbow Six Siege is developing Killzone 5 which is fine by me. I do hope they evolve it. Wide-linear levels, maybe some melee combat, better stealth, etc. It does need to evolve if it returns, that's for sure.
As for Horizon Zero Dawn, I truly prefer it to stay as a solo single player story driven game. We have a great protagonist in Aloy who simply needs more depth to the character and adding a second player would completely ruin it in my opinion. Playing Far Cry New Dawn now just like Far Cry 5 a year ago and just no. Any kind of character creation and/or silent protagonist just doesn't work as it kills off any potential the story would have.
As a separate online multi-player mode or some kind of separate co-op mode is fine as I could easily ignore both and it wouldn't affect the story and characters. Games that have co-op and/or online multi-player especially in the story campaign just doesn't work from a narrative standpoint because the story ends up being shit every time.
Not to mention the fact that Horizon is an action RPG and to me, after gameplay, the story, narrative and characters need to be top notch otherwise, it's just "another game".