The climate thing is honestly a culmination of 2+ decades of a vast gamble between US and China. US gambled that fracking would be the future, while China gambled that EVs and renewables would be the future.
This gamble can be credited as one of the major factors that flipped balance of power over to China. Probably if the roles were switched, the balance of power would be much more even or even favor US today. Whoever adamantly drove the fracking politics in the US did a huge mistake, while those pushing for renewables in China demonstrated great foresight.
I think Trump's anti climate position is simply a tantrum at having lost the gamble. They're not presenting real solutions or making an attempt to rally. Instead, they're just doing ostrich tactics by refusing to engage with any of the new tech. It's incredibly self destructive.
Trump's anti-climate position is simply because he is living in the past and always has been. He has been opposed to any new technology, and especially if his political opponents support it, he would oppose out of spite. There's no deeper reasoning behind Trump's personal reasons beyond that.
At a more systemic level, the fossil fuel industry oligarchs have a stranglehold and they lack the vision to move into the future, and instead try to continue their current status quo in order to keep their profits rolling in with relatively minimal effort. Changing would require actual significant effort and temporary decrease in profits.