In turn, I find the typical comparison platform estimate hard to believe. I live in a 2-person household and we need roughly 1000kWh/a without really caring for it. The platforms estimate 2500kWh/a.

Even with an extra freezer and a dishwashing machine we wouldn't come even close to the "estimated" value. Also: We pay about 0.25Eur/kWh. The 30-40Eur/mo is also true for us.