Not a threat necessarily. Some energy companies and miners stand to benefit. That's pretty much it. If they are coercively and arbitrarily allocating a certain amount without taking into account the state of the energy market, this is a bad idea and will cause misallocation. Electricity consumers will be affected and might face shortages or price increases. Private grids that allocate capacity to Bitcoin mining according to supply and demand will be an incredible grid stabilizer. Demand response requires there to be an adequately market-based energy allocation system. This ain't it.