This comment packs a surprising number of misunderstandings into a single short sentence.
China outlawed crypto mining early last year, resulting in a two-thirds drop in the hashrate within a month. Even then, the order of magnitude was wrong for it to be "the best way of exporting coal," which by the way China is a large net importer of; https://ccaf.io/cbeci/index estimates the whole Bitcoin network at 14 GW, but China's electrical production averages 850 GW, and overall energy consumption is some 4500 GW, 2500 of which is still coal.
So, at best, China could only have been exporting about 1% of its coal consumption in the form of Bitcoin (though in fact much of its Bitcoin mining was renewables-powered), and now it has mostly stopped doing even that.
No, according to https://www.bbc.com/news/technology-57811959, only about 7% of the hashrate moved to Kazakhstan (probably about 1 GW), which (according to https://en.wikipedia.org/wiki/Energy_in_Kazakhstan#Electrici...) only has about 10 GW of total electrical generation (out of 20 GW capacity). Coal just isn't competitive for bitcoin mining unless you can get someone else to pay for it, even when the plant is already built, so Bitcoin miners are in no position to fund the expansion of Kazakhstan's coal-burning generation network.
The hashrate fell 53%, hitting bottom in July, didn't finish recovering until December, and still isn't consistently above its pre-prohibition peak, so "much of the drop in the hashrate" wasn't picked up by anybody.
China outlawed crypto mining early last year, resulting in a two-thirds drop in the hashrate within a month. Even then, the order of magnitude was wrong for it to be "the best way of exporting coal," which by the way China is a large net importer of; https://ccaf.io/cbeci/index estimates the whole Bitcoin network at 14 GW, but China's electrical production averages 850 GW, and overall energy consumption is some 4500 GW, 2500 of which is still coal.
So, at best, China could only have been exporting about 1% of its coal consumption in the form of Bitcoin (though in fact much of its Bitcoin mining was renewables-powered), and now it has mostly stopped doing even that.