Arguing that energy sustainability changes have made people worse off because they've reduced per-capita energy use is blatantly begging the question. Maybe energy is being used 3x as efficiently as it was in the 90s and so people are 2.4x better off.

They'd still have a better lifestyle if they used the same amount of energy and used it more efficiently. The lifestyle Germans enjoy is falling behind a hypothetical world where they implemented a cheap energy policy.

How much energy they produce is much more important when assessing how their renewable transition is going. They have barely managed to tread water by doing less per capita and matching their old supply. This is a far cry from the optimistic touting that solar/wind was a viable market competitor to fossil fuels - the evidence here is that these forms of energy are worse.

> They'd still have a better lifestyle if they used the same amount of energy and used it more efficiently.

Only if you're assuming some kind of linear relationship between energy consumption and happiness, which seems extremely dubious.

Maybe not happiness but definitely living standards. In the US air conditioning systems are common in Germany not so much.

Right but you can't jump from that to assuming that US homes are nicer to live in - the difference is at least partly because more solid construction, traditional styles, and environmentalist design mean that German homes passively hold a comfortable temperature better than US ones. Air conditioning is a very brute-force solution to the problem and it comes with a significant downsides (noise, dry air that you then have to add more appliances to address, ugly, have to keep your windows closed...).

Lots of housing in Germany is well-insulated enough that AC is not needed. This argument seems dubious.