>Meaning it's silly that metalbending can spread to the point nameless cops can do it.
> Just like how nameless, poor factory workers can lightning bend for multiple hour long shifts daily.
In defense of these things, I think it was a consequence of how much information(bending styles and secrets) spread with the advancement of technology(printed books, newspaper and radio). Take lightning bending, in TLA it's treated as this super advanced form of fire bending, that can only be used by those who are in total balance. Truth is, this was something only known by the royal family, and some servants(those twin hags that helped Azula), and only taught to them, thus there were few people with the knowledge. Furthermore, they were probably all about tradition, and doing it exactly as their forefathers did, in the exact same way, same training, same technique. It might have actually been a really inefficient way of lightning bend, but there were too few people to experiment new ways of doing it, and they were discouraged from doing it, because of muh tradition and spirituality. After TLA, technology progressed, books were printed, and now every firebender knew the secret, but most couldn't do it. I believe some of them, figured out some hacks on how to quickly develop the skill, without needing to be in balance, however it wasn't as good as the original form, let's call this chinese lightning bending. So the chinese version quickly spread with books and newspaper, and now even more people could do it, and some of them developped even cheaper and dirtier modes of doing it, let's call this indian lightning bending, which spread further with books and now any fire bending smuch off the street could "master" it in a month. It is a degenerate form of the original, that can not hold a candle to it, but hey, 8 year old Jose can now do the cool lightning trick.
Same things with cops, most could, at best throw a metal disk with lots of dirt in it, but if you wanted a real metal bender, you had to go to the Toph family.
What is ridiculous with the power plant, is the idea that they would supply the electricity of the city, with some guys throwing lightning at a generator. Surely there needs to be a conservation of energy somewhere, where do those firebenders get the energy to lightning bend for several hours? Do they eat a hundred sandwiches to get the calories? Is spiritual energy "infinite", but that can't be, since we saw benders get tired, so they at least need to rest. Do they work for 10 minutes straight, rest for 50 and go back? Why are they even standing so far away from the generators when "working" All that lighting is wasted in the air, they should just touch the generator with their hands, or stand a few centemeters away, not meters away. What happens if a few of them call in sick? Can they no longer power the city? Why even do this, when you could build a damn to power the city or use wind mills(something that has existed, in our world since at least ancient times)?