Of course, it's just that, as you correctly point out, North Korea's technology is very far behind. While I'm sure they can actually cause a lot of damage still (although if they do, they'll be wiped out themselves very quickly) the fact is it's more fun to make exaggerated jokes about their technology than it is to panic
They are far behind, but if you look at this history of the Korean war, it was the opposite. North Korea was far advanced in technology over South Korea.
Though the South had help from some of the finest in the world.
That being said, South Korea and their allies will follow a fairly strict code of war. Abide by the Geneva convention, and try to strike precise targets.
North Korea will shot at anything that moves, anything that doesn't move and anything that's surrendering. I am sure they will be using extreme torturing techniques.
We can only hope that North Korea will have a lot of defectors and only want asylum and food.