It's only an id tech game even. It's by MachineGames, who're basically a bunch of ex-Starbreeze developers. Now, Starbreeze did a few good games like The Darkness and both Riddick games, but they also made less than impressive stuff like Syndicate, so it's a bit of a mixed bag.
Even if Carmack were still at id (and he was for the vast majority of this game's development cycle, remember), he probably would've had little involvement. Not that I feel like it matters, though. Carmack is an amazing programmer and engine developer, but he's not very good at designing games from that tech (as can be seen by the fairly middling output id has had since shortly after its early days).