My pet theory, if we indulge in a bit of conspiracy theory about the oligarchs, is that they're in fact benevolent and that the final outcome with be a net good for humanity in relation to the climate challenge.
I mean, Trump is so blatantly destroying american influence that it would be hilarious if it wasn't so tragic. When you think about the alternative, that is, a "regular" american elite saying that climate action is important with their regular hypocrisy, pretending to be doing anything at all, but in fact going the other way, then things don't look so bad in the medium term. Sure, a bit of short term pain, but otherwise, might end up being better off.
I mean, try to put yourself in the shoes of one of those oligarchs a few years ago and ask yourself how you'd actually solve the climate problem, given current cultures around the world. Maybe you'd come up with the "let's prop up Trump".
That being said, it's just a pet theory. I actually have doubts that such smart oligarchs exist.