Energy and time are the primary inputs for all production, only limited by what materials you can acquire to use the energy to produce. So it's a good point - cheaper energy naturally means more mining, probably. But the game theory dynamics are pretty well proven in how things have played out since the inception of Bitcoin. It usually is almost as profitable to build to sell as build to mine, though specialisation in both is unlikely. So, while it would lower the cost of mining, and probably attract more miners, and enable more miner production, it doesn't change the Nash equilibrium that is also part of the "one shot principle" about money and digital scarcity.