In AnJ you watch a homeless 15 year old get tossed into jail for petty crimes. Doesn't care that he's locked up because he has nothing to live for - no family no friends no ambition, nothing. He gets introduced to boxing through inmates, a coach who sees potential in him, and a rival who whoops his ass with pure fundamentals. Joe gets out of jail determined to return the favor to that rival and dedicates everything he's got to boxing until nothing else is left to give. In return for his dedication he gets life discipline, companions, champion success and the support of a nation inspired by a man who went from nothing to something. This is the best character arc in any anime ever made. And you watch AnJ for his journey.
Ippo probably doesn't exist without AnJ. But that doesn't mean they're similar in major ways and doesn't mean that an Ippo fan will automatically like AnJ or vice versa. In Ippo Takamura is a legend who never loses to anyone despite how odds may look stacked against him. Literally beat a Bear with his bare fists. "Takamura always delivers" is the one constant of Ippo and everyone who watches it loves him. Well imagine if he were a vegetable after the Bison fight. Go from a champ of unlimited charisma to a guy who no longer has functionality of limbs and can't even remember his own name. AnJ puts you through this experience three separate times, and all of them are gutwrenching to the viewer. To the point that you might have to pause the anime for a day to get over what just happened. Much more realistic about cumulative damage sustained by fighters who enter the ring in poor health conditions, and the realities faced by professional fighters who dedicate their lives to an unforgiving sport. Ippo is funnier, AnJ is more brutal and doesn't pull ANY punches on characters regardless of how much fans like them.
Japanese communities held a public funeral when one of those characters died
this sounds retarded on face value...and probably still even when given the context. but these characters were designed to represent values of Japanese working class culture and inspire those who see themselves in their personalities. Huge, HUGE influence on the industry and attitudes towards anime going forward as not just fiction, but a representation of culture itself. Anime nor manga is not the same without it.
AnJ does have the disadvantage of airing in the 70s. The first season is an eyesore to look at. Even compared to the standards of the period Lupin looks way better by comparison. So you do have to tolerate bad sound quality, looping animations and tons of panning shots. But the second season gets a visual makeover and from there its easy sailing. The manga on the other hand has great quality from start to finish, and is probably the medium I'd chose to start the series if anyone is interested in doing so to save themselves the time.
This is the 2nd best anime I've seen to Legend of the Galactic Heroes. Not something I'll recommend to everyone since you do have to hop in a time machine and deal with old animation to get started, but if you can deal with that and do care about character driven narratives then is a pretty easy 10/10 that remains one of the GOAT anime even fifty years post production.