If Horizon had antagonistic Dinosaur assholes haunting me like the War Chiefs in SoM (or better yet: some non-cosmetic idea to call its own) I might actually enjoy it. As it is, it's just a really pretty pastiche of countless open-world game that came before it, and for the life of me I cannot understand what's so special about it.
You may not like this but this is a combination of open world mechanics that is very popular with lots of people - possibly except towers but you don't need to do the Tall Necks (towers) in Horizon, you can just explore and reveal the map. I always liked the Ubisoft formula found in Assassins Creed, Far Cry and WATCH_DOGS. My dislike of older AC games was not related to the formula but crappy combat and crappy missions, long since fixed IMHO. I like having an open map to explore, with some variety and some side activities for variety.
But even within the Ubisoft formula, Horizon has utterly satisfying and varied combat, great characters and an interesting story to tell. More importantly it's not doing the Uncharted thing of wresting control from you every 10 minutes to throw you a QTE because it wants to be like a film. I loathe the scripted environment crap which is overly pervasive in Uncharted 3, Uncharted 4, Rise of the Tomb Raider and other games.
Maybe it helped I was a skeptical of Horizon, given the gameplay looked repetitive and I hated the stories and characterisations in the Killzone games. You can argue the gameplay
is repetitive but the second-to-second combat is just so damn good for me, just like the driving in Motorstorm. I didn't; mind losing a race in Motorstorm because driving was so much fun in itself. Combat is like that for me in Horizon. It's satisfying to take down a dozen things stealthily and it's satisfying when things go tits up and go super chaotic.
I gelt much the same about Shadow of Mordor.