Adaptation Displacement: The movie is undoubtedly more well-known than the original manga, in part because the source material had a really screwed up release. Marvel Comics bought the rights to translate it/bring it over to America when the movie was released in the US in 1989, but Katsuhiro Otomo's decision to redraw the last 1/6th of the manga led to the US version seeing a massive delay in the publication of the last eight issues and by the time the last issue came out in 1995, the series was out of print as well as the trade paperbacks, of which only 10 of the proposed 13 volumes ever saw the light of day. It was not until Dark Horse Comics got the rights to the series in 2000 that the manga received wide release, in terms of availability.
Darkness-Induced Audience Apathy: Given that the story is set in a post-apocalyptic world where violence and corruption are rampant, with nearly every character being a reckless criminal, an authoritative megalomaniac, or a helpless victim suffering from poor living conditions, it is entirely possible for an audience member to become completely hopeless and indifferent towards their struggles. The fact that many of the characters look very similar to each other visually does nothing to help viewers distinguish between those who are at least somewhat likable and those who are simply not likable at all.
Designated Hero: Kaneda, at least in the beginning. Moreso in the manga, where he doesn't have any remotely heroic traits until about the second volume.
Tetsuo crosses it when he kills Yamagata in the film and manga; earlier on in the manga than in the film.
The executives on the council cross it when they put an investigation into Colonel Shikishima's supposed scandals over the security of Neo Tokyo. Being put under arrest only convinces Shikishima to take immediate action and execute a coup d'état before the corrupt council can do any further damage.
The Woobie: Kaori. She's one of the few characters who actually loves and cares for Tetsuo and for simply liking the guy, she was molested by a biker gang that was rivals with Tetsuo's, is constantly shown to be in a state of sadness due to all the crap that happened to Tetsuo, and is rather cruelly killed off at the end. Tetsuo himself would be here on this list too if not for his more villainous actions.
Tough Act to Follow: AKIRA was such an influential and massively successful piece that Katsuhiro Otomo never rose to the same level again afterwards. To wit, The Legend of Mother Sarah which he wrote and completed afterwards was also popular and took much longer to complete (16 years) but was always overshadowed by its predecessor, despite its high-brow and intricate plot. Likewise, his first major manga Domu is also not as known despite its quality.
And You Thought It Would Fail: While they were both fans of the film, Steven Spielberg and George Lucas thought the film would be unmarketable in the United States. The movie became a cult hit, and its arrival in the West became one of the defining moments in leading to the growth of the anime market outside of Japan.
Despite the original release having warnings that it was not for children and the re-release being rated R, you can still find stores that put this in the "family" shelf. Other stores at least put it in the dedicated "Anime" section, leaving it to the person browsing the shelf to at least use their own discretion when searching for stuff to show their children.
The movie is sometimes cited as the one thing that first proved there was potential for animation beyond the ghetto.
Awesome Art: Dear GOD, YES! Even people who aren't fans of the film won't deny how stunning its animation is.
Gateway Series: Towards adult-oriented anime and animation in general. Remember, the movie hit western theaters around the time that The Little Mermaid (the film that kicked off the Disney Renaissance) was first playing, so its arrival outside of Japan came at the perfect time.
China's aggressive invasion of Japan hits a little close to home with China building staging point islands starting in the early to mid 2010s.
A blurb in the manga claiming that the World Health Organization was being criticized for its handling of a pandemic was even more prescient in 2020 during the Coronavirus crisis.
In addition, the story is in a backdrop of the 2020 Neo-Tokyo Olympics, and Akira was apparently buried below the unfinished Olympic stadium. On September 9, 2013, Tokyo was selected as the host of the 2020 Summer Olympics, which would almost happen... until the coronavirus delayed it by a year.
The violent anti-government demonstrations/riots depicted in the movie have become this in 2019 in the real world with the anti-government demonstrations in Hong Kong and moreso in 2020 with the widespread anti-Police Brutality demonstrations in the USA.
Mainstream Obscurity: The film is very iconic, but there are plenty of people who are familiar with the major scenes and the memes they've spawned (see below) but have never actually watched the movie themselves and have no idea what the plot is about.
Romantic Plot Tumor: Just narrowly averted with Kaneda and Kei's romance, because it's not really developed that much onscreen.
"Seinfeld" Is Unfunny: The 1989 dub, which was well regarded when it first came out, but is disliked by newer fans who are used to hearing the 2001 dub or original Japanese audio. Likewise, older fans who are used to the 1989 dub dislike the 2001 dub.
Signature Scene: The one scene where Kaneda stops his motorcycle. It's the single most famous scene that has been homaged countless times and will be remembered forever in pop culture. Bonus points if they use their foot as a brake.
There's also Tetsuo's mutation at the end of the movie.
They Changed It, Now It Sucks!: Many fans of the manga have this complaint because the film tries to cram the first third of the manga into a single movie (many for first two acts it has plotlines following three to four characters at a time) and doesn't use the rest due to a divergence in plot.
They Wasted a Perfectly Good Character: Kaori is Tetsuo's girlfriend and probably one of the few people who really understood/cared for him. She only gets a few lines and screen-time before being killed off unceremoniously.