I am sympathetic to this argument in theory. Privatising an essential good was madness to me and the evidence is in. It hasn't worked. electricity prices are higher than otherwise would be. It is disappointing that institutions such as the Productivity commission cannot even admit they made a mistake when they champion privatisation.
However in practice you cannot uncook an omelete. No State Government is going to spend money to buy back electricity assets.
On a related topic here John says now-is-the-perfect-time-to-increase-coal-royalties-to-fund-australias-energy-transition