With regards to the environmental cost of Bitcoin surely we need to consider the bigger picture.

The cost of acquisition helps give it value.

The initial impact was probably never imagined and is being solved with newer projects.

The environmental impact of creating, mining, transporting, storing & protecting cash, gold or any other store of value is probably equally large.

Bitcoin is an easy target because some people simply don't like it. Why don't the same people complain about the 'unnecessary' cost of using computer power simply to render a film or game purely for entertainment? We waste resources on things far less important or revolutionary than Bitcoin!