When the original manga was published, the story happened in the "now" back then. This means that Max and Griffin knew each other in Vietnam and that Ash gets involved with the Banana Fish investigation around 1985. Of course, if Max and Griffin were still Vietnam Veterans that would have made them 61 at the very least, which would make Ash and Griffin's relationship quite hard if Ash was still 19 at the beginning of the story.

So the anime solves this by making Max and Griffin veterans from “a war in the East”, without actually being specific, and moves everything else to 2018 so that the newer audiences don’t wonder about really old computers that can’t connect to the Internet. That brings a different set of problems to the table, but we’ll talk about them later on.

Arthur is one of the first obstacles Ash has to face. It’s quite obvious in both versions of the story that Arthur wants to be the leader of the gang and Dino Goldzine’s second in command. This makes him disobey Ash and do whatever he can to get him and his allies killed. In the manga, Arthur does his best to undermine Dino’s confidence in Ash, going as far as to frame Ash for murder so that the gang leader will end up in jail. But in the anime, Arthur doesn’t need to do this to earn Dino’s trust, he does it directly under the mob boss’s orders to teach Ash a lesson.

This may look like a small change, but in the bigger picture, it’s quite important as it completely changes Arthur and Ash’s relationship, as well as Ash and Dino’s. With Arthur following Dino’s orders from the beginning, that means that even if Dino planned to adopt Ash and make him his heir, he never quite trusted Ash Lynx nor thought he could really control him without help.

One of the main problems of adapting a 19-volume manga into a 24-episode anime series is that some very important things are going to be left on the cutting floor. This is quite obvious when Ash is in jail, because if we go by the anime timeline, it feels as if he was there for a week, one day in solitary, and having quite an easy time that gave him the opportunity to plan his next moves. In the manga, however, it’s quite clear that he stayed there for at least two months, three days in solitary, fighting for his life every day, and even got an AIDS scare as he was the victim of abuse from his fellow inmates. Needless to say, some fans are quite happy that that little bit never got adapted.

About 70% of the conflict in the Banana Fish manga is because the characters can’t easily reach Ash or Ash can’t reach them in order to exchange important information. This is, in fact, what causes the tragic ending because there was no way to inform everyone that Ash hadn’t really betrayed Shorter, and thus, there were members of the Chinese gang that still wanted Ash’s head. However, in 2018 most of that information, including the fact that Dino was the real culprit of Shorter’s death, would be easily shared with a smartphone. And don’t try to tell us that gangs so organized and with ties to the mafia and the Chinese mafia wouldn’t have smartphones. They probably have the latest model as burner phones.

The anime adds as many scenes as possible to make sure we know that everyone's phones are ruined or useless in the most critical moments, but it still makes them look a bit silly in a world where we know there are bulletproof cases. The story is still intriguing, but we have to ignore that we live in a world where everything ends up on Twitter in seconds in order for it to really work.