There are some who consider any use of electricity for Bitcoin mining to be wasteful. If you extrapolate, the problem is either, 1) They believe that they should be able to decide what electricity can be used for, or at least through the democratic process, or 2) The belief that all electricity usage is ultimately a waste - that humanity is somehow destroying the earth with every electron generated and consumed - and as humanity we must reduce electricity consumption to 0.

On point (1), New York recently tried to ban Bitcoin mining, and it failed with a combination of lobbying by the industry and the electrical unions. Support for it with politicians collapsed. This is literally the democratic process, so if it didn’t go your way, you should support it. If alternatively you want a dictator (yourself or others) to ban it because of your perceived notion of what is a “good” use of electricity, I don’t know what to tell you. Move to China?

On point (2), this is a Malthusian argument. As a society we should be happy when more energy is generated, as that shows development. The total consumption of electricity is a reflection of how developed we are. Environmentalists should promote the generation of cleaner electricity rather than the outright ban of usage.

The bottom line is, electricity should be generated and offered to the market. Your subjective opinion of what is a “good” use of electricity is meaningless, as I find video games, jacuzzis, air conditioning, and all manner of other uses of electricity a waste. So you saying Bitcoin mining is a waste is just a simple opinion.