Despite increasing evidence that North Korea is not actually interested in denuclearizing (as anyone with a brain expected), Trump prefers to remain in denial about it, effectively appeasing North Korea. And that’s arguably a good thing, because it beats the most likely alternative: Trump throwing a temper tantrum and starting a war in retaliation.
Effectively, very little has changed with respect to North Korea. This is because there is simply not much the USA can do about the situation. Not all problems have easy solutions, and North Korea is (for a variety of reasons) one of those problems.
Which, in fact, is why so many past administrations “let” the problem get to where it is today: they couldn’t easily do much about it, either.