The way crypto mining works, the whole point, is that if a billion CPU cores are trying to mine a coin, one and only one wins, and gets the coin.
The results of the other 999,999,999 are scrap and get wasted -- their results are heat and fossil fuel emissions.
It is literally the least efficient use of computing power in history. And that includes LLMs which ostensibly produce a "useful" result each time.
We should outlaw crypto mining through the EPA. For a start.