Decreased shipping wont change the culture of consumption - that will only end when the culture changes. My loosely held belief is that the ecology of the planet will only be saved because of capitalism.
We will only get to a sustainable ecology when 1) solar power provides energy for less than fossil fuels, 2) the majority of human women have control of their fertility, and 3) the majority of humanity's basic needs are fulfilled enough that they can worry about the environment. #1 will lead to less pollution and climate restoration, #2 will lead to decreased or sustainable global population, and #3 will lead to the preservation and restoration of ecosystems. All of these things are only possible because of the wealth generated by capitalist economies.
We will only get to a sustainable ecology when 1) solar power provides energy for less than fossil fuels, 2) the majority of human women have control of their fertility, and 3) the majority of humanity's basic needs are fulfilled enough that they can worry about the environment. #1 will lead to less pollution and climate restoration, #2 will lead to decreased or sustainable global population, and #3 will lead to the preservation and restoration of ecosystems. All of these things are only possible because of the wealth generated by capitalist economies.