I could only fathom it's some "it's not Rocksteady so it must be worse" thing where they focused on every single flaw and the fact that half of the map is "reused" and demanded innovation for innovation's sake. I mean you have how many outlets and reviewers that gave the first two games 9.5's, 10's, five stars, etc. So I could see knocking it down to 8.5 or something. (Like Call of Duty always seems to get.) But that 73 metacritic is just strange. It's basically the same exact gameplay, just more of it, in new and old scenarios.
And then you have guys like Tom Chick who refuses to even play the game saying he has no interest in it especially now that he's heard it's horrible when he was orgasming over every inch of Arkham City just two years ago. (And he wasn't the only one like this. Giant Bomb practically never even mentioned it.)
It's one of the stranger things I've seen. "I loved this stuff, Batman is amazing! Ugh, more to play? No thanks."
I also don't get the complaints about the writing, especially compared to the first two. Arkham City was a mess plot wise, Asylum had plenty of stupidity, I thought this one's main story was fantastic after Copperhead. The Joker was that perfect balance of mad, deadly and having a delightful time. They nailed his desire to "play" with the little dashes of his rational "dark" side and the great usage of laughter at inappropriate times. He's doing insane stuff with Bane in the Hotel and during the final gambit but he's having a good fucking time. And I thought they did well, although a bit over the top and ham-fisted and not too well fleshed out, to deal with the idea of how this is something new for Batman and he hasn't really wrapped his mind around it yet like everything else you just handle easily in the game.
Could it have used another year of development to better develop that strain and make better use of the assassins, and add some life to the open world, not to mention polish things up? Yeah, of course. But it's not like they just dumped out garbage. If anything the game made me more hopeful for the future of the franchise and the Suicide Squad game. Rocksteady's base is really...lol nope
The multiplayer though, like Brink (and ET:QW!), has some cool ideas and at times could be very engaging with the heroes involved in the mix, but the execution is just terrible. And somehow Splash Damage is getting worse at things like stability and netcode it seems like.