Yes.
I bought KF Ancient City on a whim back in the day, brought it home and started it up and my immediate reaction was, what is this shit.
But a week later, I decided to give it another shot. And it wasn't cuz I was a kid and had no other choice, I mean I was a working adult so I could have just brought it over to Gamestop and traded it in for something else.
Well, it sucked me in somehow, and before I knew it I had spent something like 20 hours on it within a week or so.
It's hard until you learn how to play it. You need to learn PRECISELY the range at which you can safely attack. You also need to learn how to strafe around enemies to get behind them so you can attack safely.
Once you learn all that, it's got a really amazing atmosphere, and it is not dumbed down for ANYONE. I mean, these are the people that eventually went on to develop the Dark Souls games (probably not the same exact people). The game gives you no maps, no help whatsoever, but the level/world design is so memorable that you almost don't need any maps. Having said that, it is much more "mazey" than any Souls game, so drawing maps wouldn't hurt.
The game is full of set pieces, without actually doing set pieces. It's like a cool guy who is just cool without trying. All the other games are doing elaborate cinemas and railroading you into situations to create set pieces. KFAC just throws you into a cavern full of gravestones, and when you get to the top a million skeletons rise to destroy you, and you run the fuck out of there. And it's all up to you. I also remember carefully hoarding my resources until I finally revived some spring or something that let me refill some healing item (and a shortcut back to that spring I think), and the relief I felt was not just for the character I was playing. It was like, okay, I can finally relax a bit. They know I can play the game, so they are finally giving me a fighting chance.
And the music is amazing, it's a huge part of the atmosphere.
It's not an easy game to love, but if you learn how it plays and put up with its quirks, it will repay you in spades.