That's just it, I feel like I've gone over the Nirvana story enough already....but every time a new perspective comes in, I get something else new.
If there's one moment in D&C that is completely and unutterably true to the adolescent experience and that cannot be accused of artifice in any way, it's less the fight scene than the incident that provokes it. Goldberg mutters a meaningless inoffensive remark and some hick looking for a fight threatens to kill him over it. Lost track of how many times I saw that during my own small town adolescence. Was threatened a few times over minor remarks myself, too. The detail of the Nicky Katt character being too old to be hanging around with teenagers is a terrific detail, too.
The Goldberg character is supposed to be an intellectual in an environment that absolutely could not care less about politics or intellect, and Linklater said that the fight scene is effectively punishing him for trying to go out and get into visceral experience instead.
It's also meant to counter the revenge the bullied kids get on Ben Affleck, who gave one of the most accurate performances in the movie himself.
There was a fair share of 70s nostalgia in the 90s, decades usually revisit the decade two decades prior. Travolta's comeback, Michael Crichton's comeback, Tarantino, bell bottoms coming back, Boogie Nights, grunge covers of old 70s tunes, etc. etc.