Their military is crumbling due to a lack of proper maintenance, their soldiers are starving almost as badly as the populace, abusive treatment just means abused soldiers—not tough soldiers, and if you think Saddam’s generals were afraid of him, then you can’t even imagine how scared Kim’s generals are of his royal fatness.
It would be messy, but I don’t think it’s as dire as you believe it would be.
North Korea has over 10,000 prepositioned artillery pieces ready to fire on Seoul in less than 5 minutes. And in case you’re wondering about a pre-emptive strike on them... they are all built into mountain/hillsides, protected from aerial strikes.
60+ years gave them a lot of time to construct protection for their first-strike capabilities.
If the balloon went up, Seoul would be completely destroyed in the first 10 minutes of the war. And half of the entire population of South Korea lives there... or in it’s suburbs.
That’s 26 million out of approximately 52 million South Koreans.
There’s no good options with North Korea except possibly an assassination... or perhaps bribing the top, non-Kim family, military members to revolt.