Note that bitcoin mining does not primarily exist to increase the amount of bitcoin in existence. That's just part of the incentive to mine.
Bitcoin mining exists to timestamp transactions so that the network can achieve consensus on the state of the ledger. It is designed to use as much energy as possible, so as to make it expensive to cheat.
In fact, in the white paper it's just described as the decentralized time stamp server and that's its entire purpose. The term "blockchain" and all the hype about its magic powers came later.
