There’s no solid reason given for the sudden change of mind. The budget has been under constant scrutiny, very little casting has been secured, and a script that still needs “ironing out”. With all these issues on such a high-interest project, Warner Bros. seem to have killed it for now, and here’s hoping it can stay dead.
Akira currently has only one film adaptation, directed by the very person who wrote the original manga, Katsuhiro Otomo. And it certainly doesn’t require a “Hollywood remake”, least of all one staring Kirsten Stewart!