The opening scrawl mentions the second decade of the 21st century, but the date stamp once the movie begins says, "The Internet 2021". 2021 would be in the 3rd decade of the 21st century.
What are the differences between the International Version and the Japanese Extended Version?
A
Because of Takeshi Kitano's role, there was a different edition released in Japanese cinemas and DVD-shops than in other countries. But there have not only been added new scenes, instead the original version was seemingly used for another version in Japan. The difficulty of Johnny willing to get back his memory is less important here. Instead the film focusses on Takeshi Kitano's ambivalent character. Due to the different version and the fact that the Japanese edition is much longer, there are several other advanced scenes or new scenes included. A detailed comparison between both versions with pictures can be found here.