The idea of “Saving the Earth” is fundamentally flawed. The Earth is a planet, essentially a clump of inanimate minerals orbiting in space. The Earth would fine even if all of life cease to exist. It’s going to be fine until the Sun dies. It may even be fine after that if it manages to dislodge from it’s orbit.
What we are saving, is the environment which we have grown accustomed to. We save fossil fuels to sustain our transportation, we save water to sustain our agriculture and we save wastage to preserve land for infrastructure. If all of us go back to being hunter-gathers, then nothing needs saving.
We exploit the Earth greatly to support our modern lifestyles, which truthfully, is probably what we really are saving.