The point is that if energy is produced using non-fossil-fuel sources, then increasing energy intensity of industrial processes will not necessarily output more CO2.
That is, using coal power to make make energy-intensive mushroom-based packaging is probably ecologically net-negative, but if you can use solar or geothermal power it might not be.
That is, using coal power to make make energy-intensive mushroom-based packaging is probably ecologically net-negative, but if you can use solar or geothermal power it might not be.