I think the thing I often see missed in these discussions is the cost and time burden imposed by regulation. It's nearly impossible to build power plants in the US today. Launching satellites while hard, solves this problem.
Even if it's more expensive, Spacex will be able to deploy hardware when no one else can because all the gas turbines and existing power plants have been exhausted and the lead time to build new ones is 5+ years out because of the bureaucratic overhead.