>>13156481青is a vague kanji is what is boils down to. Since it comes from Chinese, it shares the issues the Chinese word has with distinction between blue and green. Depending on context, 青 can be either green or blue (example: a "green apple" is referred to as 青りんご). 緑, however, is more specifically "green" and is relatively newer than 青. Also, Japanese is not the only language with an issue between blue/green.
To make this slightly relevant to the thread, here's a flipnote studio animation I did on the 3ds version that Japan got recently. (still gonna sage tho)
