I agree it's rather strange to ask for who has the lowest energy usage when you're a cloud customer. "I want to rent this computer to do X, but it shouldn't consume any electricity" is not a reasonable demand.
However: one could say that these companies are now big enough that it is reasonable to start demanding that these companies source the energy in a climate-friendly way. I think it's not at all unreasonable to demand that when Google or Amazon builds massive new data centers to be responsible about how those data centers are powered.
However: one could say that these companies are now big enough that it is reasonable to start demanding that these companies source the energy in a climate-friendly way. I think it's not at all unreasonable to demand that when Google or Amazon builds massive new data centers to be responsible about how those data centers are powered.