More like social engineering.
Anyway, if you're a crypto developers, I think you should realize that you should not install anything recklessly to any of your machine that can access important thing like server and so on.
If you keep installing these random things into your machine anyway, do you really fit to be a crypto developer where security is like the primary concern?
You might be right, but the thing is that sometimes we just have that one slipped and everything falls. There are some of blindly trust anyone and that is one mistake and this is a human factor that we really need to overcome. As for the North Korean Hackers, if I'm not mistaken, it was just the West that put the blame on this. We really don't know if such group really exists. There are also school of thoughts that the West might have created the Lazarus group out of thin air and blame everything on the North Koreans as far as hacking crypto and any services.