Well sure if you happen to live somewhere that has 100% carbon neutral electricity - but in that (very rare) case the electricity use for mining Bitcoin without heating your house is also not an environmental problem. In reality, the vast majority of Russian electricity comes from fossil fuels.
Turning gas into heat is very efficient. Turning gas into electricity and then into heat is not. Winter heating with renewables is problematic. You need to meet very strict insulation standards for it to be viable.