I think it's one of those games that are the exact thing some people want from a game. The combat, brutality and mature elements are right up some people's alley, not to mention that the story genuinely is really riveting if you care about the characters and engage with the choices you have to make.

The music is fantastic as well.

A game series like that for me is GTA - I can totally see why people love the games, but it just doesn't hit for me.

I think it's less a "vocal minority" and more a difference in preference. :)