Miners create bitcoins by solving complex mathematical problems, for this they need powerful computer equipment. In China, their "farms" are located mainly in sparsely populated suburbs with inexpensive electricity and a cool climate. 80% of the power spent on the creation of bitcoins in the last 30 days falls on China.
According to experts, the simultaneous shutdown of facilities located in China is unlikely - including because China is spinning nuts in the turnover of bitcoins for months, and many miners already could transport equipment from there.