Reductions in overall electricity consumption are not going to happen.
Cleaning up the rest of the economy - transport, chemical and industrial processes currently run of fossil inputs and so on means that the grid is going to have to supply a lot more juice. Currently electricity is roughly a third of our energy use, in a zero-emission economy, it will be well north of ninety, with the remainder being things like food production waste based fuels for niche applications and ambient heat sucked in by heat pumps. So even large efficiency gains still imply electricity production that is overall quite a lot higher than at present.
So production plans need to be scaled for that, and the main point of efficiency gains is to limit just how much additional cabling you are going to have to bury.