"Mostly by lights that aren't shielded." Overall, the lighting is still necessary, it's just not as efficient as it could be. By that standard, over 99% of Bitcoin mining is waste because because most of the power goes into solving artificial difficulty.

The only people who genuinely care about PoW are miners and a handful of enthusiasts. I'll generously estimate that 1 million people fall into this category. So you have a million people using .5% of the world's electricity just for one of their interests. Contrast that with the billions of people who enjoy videogames or outdoor lighting.