There's just something dull about Horizon. I think the issue has to be the story and voice acting more than anything. You can't release a cinematic action game with a plodding story and an amateur hour voice cast these days, the market is saturated (in no small part with Sony's own first party efforts). Ghost of Tsushima pulled it off because nobody had done a samurai game right before and that's one of the most compelling settings in fiction. Post-apocalyptic robot dinosaur cavemen doesn't exactly have the same pull.
Guerrilla should have used their development time to bring Horizon's story and narrative presentation up to a level with, say, Witcher 3. They didn't. The game is stagnant in pretty much every way and it's rightfully getting its ass kicked by Elden Ring.