Of course they will, but energy companies have a larger minimum capital expenditure than a household looking to invest in generation. And the energy company will likely still carry the full cost of transporting energy, which becomes more expensive with more energy sources connecting to the grid.

It would be a change in the dynamics of economies of scale vs small and nimble, greater lobbying power is one thing economies of scale still have a big advantage in so GP's comment seems plausible.

Exactly. There will be no need for "legacy" energy. Companies that are too invested in fossil energy can die and be replaced with companies that invested in solar.