So the problem is more a coal energy problem than a bitcoin problem?
The mining-power relationship essentially creates a price arbitrage opportunity between electricity prices and Bitcoin mining fees. This is a very bad thing for the global economy as it ties all other uses of electricity to the Bitcoin mining fees in a very direct way. I can't think of another relationship this direct to energy prices, it could be catastrophic for entire industries. Oh and also it's emitting as much emissions as Argentina at the moment.
A friend of mine called Bitcoin a candidate for The Great Filter, and I'm inclined to agree.