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Batteries store energy. That energy needs to come from somewhere.

In any case, energy is a real cost. Energy used to mine Bitcoin is energy that could have been used productively in other places so yes, it could be considered a "waste."

However, Bitcoin is by no means dying. Despite the fall in price (which is the least interesting part about Bitcoin), the hash rate continues to rise and the average number of transactions continue to go up.

Everything has a cost and opportunity cost.

Having an immutable decentralised censorship resistant platform is worth a lot of money to some people as well as miners.