Even if it was green energy (which doesn’t generate zero pollution over its lifetime by the way, we still need to produce the equipment to generate electricity and that’s a source of pollution), that’s extra power that needs to be generated that wouldn’t need to be otherwise and it’s used for something intentionally inefficient.
The miners are taking power from the same grid as everyone else. Miners don’t emit carbon. Electricity generation from fossil fuels does.
The focus should be on moving to a renewable and abundant energy grid. Then let people use it for whatever the fuck they want.
Even if it was green energy (which doesn’t generate zero pollution over its lifetime by the way, we still need to produce the equipment to generate electricity and that’s a source of pollution), that’s extra power that needs to be generated that wouldn’t need to be otherwise and it’s used for something intentionally inefficient.