With climate change, the pointlessness of individual action is especially acute. If you accept the scientific consensus on warming, then you know your personal carbon footprint is a drop in the rising sea. So, why on earth would you feel compelled to lower your quality of life for the sake of cutting carbon emissions by a wholly negligible amount?
Environmentalism-as-personal-virtue was a bad route. It isn't a substitute for collective action. People don't like being told how to live their lives, especially as you don't have to understand this stuff all that well to get that we're almost all big hypocrites. We make some easy choices and ignore the rest. We can make slightly better choices, but there's no solar powered plane to fly me to Europe.
And the virtues of many in the environmental movement are, well, wrong (#notallenvironmentalists). Dense cities are green.* The way to save nature is to stay the hell away from it. Automobile transportation is a huge driver of emissions and that is not compatible with "I want to live in the middle of nowhere with nature because nature is good." Detached homes are more expensive to heat and cool. Large homes are more expensive to heat and cool. The entire country doesn't have to look like Manhattan, but people should get that we'd get a lot closer to saving the world if it did.
*There are environmental issues with cities - local air quality because of the concentration of cars - but otherwise...