One can always post-fact construct a motive for North Korea. One can certainly think about front page worth motives for Iran too if you try, and Russia, and whoever you want.
Opportunity costs are exactly as low for every country that the US decided to antagonize by placing on their evil axys list, and only marginally bigger for any other actor, because nobody will catch the hacker.
The only item of yours that can not point to anybody that you want is the evidence. Evidence-less finger pointing is not a sane sport.
Can you come up with a good motive for Iran or Russia?
Opportunity costs are not exactly as low for every country, as they have different capabilities, use different tactics, have different budgets and talent pools, and have different interests. Triage is going to be different for different state actors. Pure and simple. I'm not sure that an opportunity cost analysis indicts NK - and in fact I do suggest that work needs to be done there in the original comment.
Even the motive for a lone wolf hacker with a huge botnet would make sense if they were impressing themselves with how good the hack was. If they could "trick" the US into thinking it was North Korea, the lulz from that alone would be enough to have the whole charade to take on a life of its own.
That's just a good a reason as any other motive for any other suspect given that I've seen.
Opportunity costs are exactly as low for every country that the US decided to antagonize by placing on their evil axys list, and only marginally bigger for any other actor, because nobody will catch the hacker.
The only item of yours that can not point to anybody that you want is the evidence. Evidence-less finger pointing is not a sane sport.