I haven't played Horizon yet but everything I've seen of it makes it look like the most 2017-AAA-western-open-world-game-ass 2017 AAA western open world game, to a fault and then some. Like they were terrified of the idea of putting any mechanic in it which hadn't already been in at least 3 Assassin's Creed games.
So I bought Horizon at launch, played past the opening area, and traded it in. My criticisms at the time mirrored what you're saying here.
I've since rebought the game on a whim to give it more of a chance and I'm definitely enjoying it now. That said, everything you're saying is still applicable, but with two notable standouts:
1. The annoying aspects of those games are streamlined in Horizon and are actually fun in some ways.
2. The characters and story have this weird vibe to them that I feel go against a mainstream AAA video game. Nothing is immediately forgettable or downright bland.
Edit: On the subject of Prey I thoroughly enjoyed it outside of the terrible PS4 control issues and the horrendous load times.
Also the best game this year is Yakuza 0 without a doubt. I can't imagine anything in the second half topping it.