North Korea has been demonized for so long that you can accuse them of anything, and everyone will believe it without question. A game that the USA in particular plays often and well, not only with North Korea.
They're an easy target when a plausible perpetrator is needed.
A discretion-minded friend of mine says they do exist, but so do others. If you read "X was hacked by North Korea" and later something happens or is published regarding X, you should not assume that the North Koreans were the only people to hack X.
North Korea has been demonized for so long that you can accuse them of anything, and everyone will believe it without question. A game that the USA in particular plays often and well, not only with North Korea.
They're an easy target when a plausible perpetrator is needed.