I've talked with a few people who didn't like it at all, and usually it's due to the same criticism: "it's way too slow, and nothing of interest ever happens."
I can see where you're coming from with this, I'm barely on chapter 3 (someone told me things REALLY pick up the pace around chapter 5 btw) and I'm finding the slower pace to be extremly refreshing for a AAA game, this game really is consuming my life, I find myself thinking about it a lot, even when I'm not playing it. I like the loot system, the world and how you interact with it, it's a really impressive package overall. It feels like a very mature game.
There's some things I don't like, I hate that you have to position the character perfectly to pick up an item so the prompt appears (Witcher 3 suffered from the same thing), weirdly the combat is sub par if you compare it to RDR1, it just feels very clunky to move and aim, you get used to it but it's a bit of a shame.