You look at the history of the sierra club. They went from an organization fighting dams and the army corp, to a group fighting neighborhood development and densification in Marin county.
You can be an environmentalist (I am) and realize that much of the 'environmentalist movement' is self-serving nonsense; e.g., plastic recycling. It doesn't mean you don't care... it just means the world is less altruistic than you thought.
The fact that they changed behavior is immaterial to whether they improved or damaged the environment on net.
You look at California’s sprawl in the face of climate change, and you have to condemn a significant amount of the cliched 70’s environmentalism movements as as much about aesthetics as they were genuinely concerned about the environment.