The Sierra Club had a group that supported halting illegal immigration because the flow of human traffic threatened the border ecosystem. They were shut down and shut up by the Sierra Club leadership who cared more about being libtards than being concerned about the environment.
The right can afford to go green and get some (probably not much) support from some lefties or at least independents who care about the environment. Any little bit helps.
Recall Michael Shellenberger’s switch. (He’s got a great Substack, but much of the info is paywalled.)
And keep in mind that many deep enviros want to enjoy nature, not live in pods eating bugs and vat grown cancer cells.