These two groups must find their common cause. As pointed out the standard meaning of efficiency is to get the most output from the least input.
Efficiency is a good thing.
I think the problem is that it does not convey any question of how much is enough. I don't know. Naming might be powerful, but because of preconceived notions, biases etc, it can also be limiting and problematic. In fact it might be better to call it a trend. As long as progress is being made towards getting people to use less, reduce pollution etc, I don't really care whether there is a nice name or not.