Akira the movie is one of the most critically acclaimed and beloved movies not only in anime history, but across movie history period.

And it still only adapted like the first volume and a half of the 6 volume manga, while cutting and changing so much that if it wasn't still fucking good it would be decried as a rape of the IP. But the undercurrents of a deeper and longer story are still there, and its part of the mystery that makes it so appealing.

This movie would certainly just be readapting the movie again, but worse and thereby not even think to add those details in while instead giving Kei more girlboss scenes to make up for it.