The elephant in the room is human population numbers. We can cease to use fossil fuels and give up eating meat in exchange for insects but until something is done to control the growth of the numbers of humans on this planet there is no hope. If one considers life on this planet as an organism composed of interdepent parts then consider what happend in the human body if one part of it starts to reproduce to the detriment of the rest. We call that a cancer and it is often fatal.