Kane and Lynch 2 was s game that had a clear vision, and interesting ideas, but had a few major roadblocks.
The Kane and Lynch name carried a ton of baggage from the first game not being all that good, and having that review controversy.
It came out at the wrong time, probably from the wrong publisher. I remember a lot of the feedback on it was that people found the over the top violence, and the overall UI/presentation being unpleasant and off-putting. Had it come out a couple of years later, when the idea of games being uncomfortable/unpleasant was something people were more accepting of, and maybe been something from a smaller publisher, maybe things would have been a bit different.
The gameplay was pretty meh as I remember it. Ultimately, it's a game, so it still has to play well. Going back to the second point though, people seem to be more accepting of middling gameplay if the game makes up for it elsewhere.
Spec Ops: The Line fell prey to that too. Pretty good storyline (even though it gets heavy handed. The loading screen messages almost made me strain my eyes from rolling them), but it came wrapped in a pretty standard third-person shooter.