You can argue that it's oversimplified, but it's definitely not inaccurate.
I'm not even sure it's oversimplified, though. Your list is a good set of things to worry about if you're going to fight a nuclear war. But from a strategic perspective, what matters is whether the capability is enough to deter, and I'd argue that even the lower end of likely North Korean capabilities is plenty, for most scenarios besides an outright North Korean invasion of South Korea. Yeah, the missiles might miss and maybe the bombs won't explode, but are you really willing to gamble with Seoul, Tokyo and Los Angeles?
Anyway --- sure, let's negotiate about missile technology. That'd be great. But those negotiations aren't going to go anywhere unless we recognize that full nuclear disarmament in the near-term is a big ask, and extremely unlikely.
I'm not even sure it's oversimplified, though. Your list is a good set of things to worry about if you're going to fight a nuclear war. But from a strategic perspective, what matters is whether the capability is enough to deter, and I'd argue that even the lower end of likely North Korean capabilities is plenty, for most scenarios besides an outright North Korean invasion of South Korea. Yeah, the missiles might miss and maybe the bombs won't explode, but are you really willing to gamble with Seoul, Tokyo and Los Angeles?
Anyway --- sure, let's negotiate about missile technology. That'd be great. But those negotiations aren't going to go anywhere unless we recognize that full nuclear disarmament in the near-term is a big ask, and extremely unlikely.