The American bipartite system is a bit strange. Ie. the "liberals" and the "conservatives." (To my knowledge there are actually other political parties as well, but for some reason I can't really understand, there are effectively just two parties in the United States.) The "liberals" (ie. "the left") seem to hold mostly just your average normal western-world values and political views about human rights, freedoms and the role of the government towards their citizens. The "conservatives" (ie. "the right"), however, seem to be populated with the most extreme archetypal American capitalist and corporatist thinking.
The conservatives are not exclusively full of gun-toting regressive rednecks, however. There are some really, really smart and intelligent people, who nevertheless hold deeply conservative values (and pretty much abhor anything that has something to do with liberalism and socialism.)
For example, there are some conservative YouTubers who are really smart and intelligent, and have tons of really good skeptical opinions about politics and social movements, opinions that are really well researched and argued, and that are very easy to agree with. Yet, at the same time, they spout all kind of archetypal extreme-right nonsense, like how liberalism and socialism is a mental disease. Or how climate change is just a hoax.
And it's especially that last part that really baffles me. You see, there's an extremely common anti-environmental sentiment among a good portion (if not even the vast majority) of American conservatives. They might say they care about the environment, but their words and actions say otherwise, and in fact they seem to vehemently oppose any kind of environmental acts and laws which would eg. reduce pollution. And of course the climate change conspiracy theory is absolutely rampant among them. They seem to think that, in the same way as they think that stricter gun control laws would mean that SWAT teams would raid their homes and forcefully confiscate all their guns, stricter environmental laws would confiscate their cars, close up factories, or something like that. It's not really clear to me why exactly they oppose environmentalism.
It's also a bit baffling where this general sentiment is coming from. However, I have a hypothesis for a possible source of it (although it might be a bit far-fetched):
American conservatives hate communism and socialism (most of them can't even tell the difference between the two, and think of them as synonyms.) To them they are pretty much like nazism, and totalitarian oppressive regimes. Many of them seem to believe that a socialist country would be like North Korea mixed with nazism, stalinism and maoism. Or something.
They also absolutely hate hippies. That's because hippies are archetypically extreme liberals, and socialists, and are all about peace and love and tolerance, and everything being shared among everybody else. Hippies archetypically abhor and oppose the military, guns, violence, and differences in socioeconomical status. And hippies are also archetypically extreme environmentalists (to the point of being "tree huggers").
And my hypothesis is that conservatives abhor environmentalism for that reason. They associate environmentalism with socialism, probably via the hippie culture (which they also abhor).
This is actually a fallacy of the undistributed middle, or guilt by association: All hippies are socialist. All hippies are environmentalists. Therefore environmentalism is an integral part of socialism. And because socialism is bad, therefore environmentalism is bad.
Most conservatives will probably deny this connection, but I suspect that this is the origin (or at least a significant contributor).