That's the not-so-funny element. Companies like Exxon were the first to hire independent researchers back in the 70s and helped pioneer climate research, with management being briefed on the as far back as 1977, and had developed its own models by 1982 that were widely circulated within the company.[0][1] That research was allowed to continue for nearly a decade, and Exxon researchers consulted on DOE research and reports throughout the 80s. It wasn't hidden, either within the company or without, until management decided to take a somewhat different approach with its lobbying efforts. They saw the word "uncertainty" with regards to climate modeling as a lifeline, and they took it.
It's easy to generalize interested parties that promote climate change denialism as not giving a damn since they'll be long dead before the worst consequences hit. That may very well be a partial explanation, but if you look at how some of the rhetoric has shifted with talk of geoengineering, there's this idea that a future generation will be able to deploy technical fixes. And once you buy into the hope that offers, it's inevitable that you'll downplay the sheer cost and scale of such an intervention. After all, computers are cheaper now than they were in the 80s, so who knows how expensive geoengineering will be in a few decades? There's a hope that an easier, cheaper solution will present itself in the future.
So I think a larger part of the answer isn't so much that corporate executives and politicians don't believe in climate change (though there are probably plenty who have bought into their own spin), as it is that they've pinned their hopes on the terribly alluring delusion that maybe it'll be cheaper to reverse the trend tomorrow than make the sort of difficult choices needed to start mitigating it today. Or, more accurately, over three decades ago.
0. https://www.scientificamerican.com/article/exxon-knew-about-...
1. https://insideclimatenews.org/news/18092015/exxon-confirmed-...
