The last time I saw knife fighting glorified in a gang-culture way was in the video for Michael Jackson's Beat It.
Last time I saw one was from a kid (17-18 at the time) at an old job of mine, who thought he was a hard little thug, and whipped it out and pretended like he was going to gut me. And when I didn't fight the kid, because we had a disagreement, one of the gangsta girls who was in his circle of friends, upon hearing what happened, mocked me for being scared, instead of just being a "hard man" and fighting him. So I wouldn't say it's not without SOME place in the gang culture, because he sure as hell wanted to seem like he was in one, and she was very much in that culture as well. There is definitely an undertone of "everything is a competition of dominance, and if you don't win, you're a punk ass ***** little cuck pussy" mentality to our society. I've had coworkers get pissed off at the most ridiculous things, that they turned into some overblown "attack on their masculinity" , even down to simply using their last name on a form, that they turned into an insult. I'm not kidding, an old coworker of mine, his last name is Walker. Our job, when clients would sign in, allowed them to mark the name of the counselor they wanted to see, if they wanted someone specific. Usually first names were used, but sometimes the client would write Mr. X or Mrs. X. No big deal. But, for SOME reason, he blew the fuck up because someone wrote Walker in that spot. And, this is HIS reason for why he was angry, "Calling someone Walker is an insult when you're in the Army, that's what you call a Private, because Private's have to walk everywhere. Ok?! I'm not a Private! I did my time I was a (whatever the fuck rank he was I forget), ALLRIGHT!? I will NOT be disrespected like that!!"
That actually happened. I wouldn't say he was "gang" culture, but he was definitely of the "Must be hard at all times, and ANY slight is a disrespect, and respect is EVERYTHING!, and if I feel I'm disrespected I have to attack the source in the most confrontational manner possible!" kind of mentality that persists in our society.
So I don't think it's knives specifically, it's the "attack all slights and insults with maximum aggression" which easily translates to "so I'm going to grab a knife and gut someone" in a lot of people's minds.