According to everything I've read and seen, Trump has made life harder for these guys. You're going to have to explain why you think they've benefited.
Apparently some explanation is still required, amazing.
Let's take North Korea as an example. The role of Trump is overestimated, early 2018, this was just Kim's two-track strategy (using Trump was just part of that strategy, he was useful). This was just Kim's two-track strategy going by the book that was prepared in 2017.
Until the nuclear missiles were ready, diplomacy was not an option for Kim. Now that they are ready, he is committing himself to economic growth. And so diplomacy ...
Trump was eager to get attention (and/or distraction from other issues), so he was used by Kim for creating a platform in the international arena for Kim. The only person who has really gained anything, is Kim.
Cheers,
Bart