> the amount of light used when moving from last-gen 'heavy industry' to next-gen 'value add'/'light industry'/'design work'/whatever is going to be reduced

Not to mention the automation of heavy industry leading to "dark factories": some Chinese factories are so completely automated now that they don't bother turning on the lights in large chunks of them. See https://www.youtube.com/watch?v=MCBdcNA_FsI