Great post, I have seen a lot of fuss made about the electricity consumption of Bitcoin mining, to be fair, as your post states Bitcoin mining does chew an enormous amount of energy. But the criticism I mainly see relates to the future viability of mining when we live in a world where we must shift to sustainable energy sources. In my view this fear is unwarranted for two main reasons;
Solar and other renewables. There is already plenty of talk about running large mining facilities using solar power, this will eliminate the majority of the environmental impact of mining but it wont be cheap to begin with.
Technological advancements. Tech breakthroughs will decrease the cost of parts and increase the efficiency and speed, when considering the pace at which tech is developing today it doesn't take long to see huge improvements.
So looking to the future the network will be virtually free relative to the current financial system with all it's institutions and buildings coupled with the fact it is also broken and as a result, extremely inefficient and wasteful. Maybe the focus should be on just how woeful the current banking system is and why we haven't moved to a decentralised monetary system sooner?