Rather, what we need is lowering humanity's total energy input. That same approach has been preached by MBA business types for decades, under the moniker "efficiency". I don't see why we can't do for energy efficiency what we've been doing for labour efficiency for decades, but it does require a more comprehensive management focus.

I don't see a-priori how "de-growth" should lead to lowering living standards, other than by implication of the (IMHO ill-chosen) word.