It just so happens that all the Austrian homes I've been in are much warmer than those in northern US in the winter. American homes are surprisingly cold.
You make what you measure.
If you compared costs to heat, and said American homes were higher-cost, that would make more sense to me.
However last winter, my heating bill in my current American home was something like $400 USD/month for maintaining a colder house than I'm used to in Europe. As someone who lived in both places, you can bet cost does play a role.
For reference my place (in Chicago) costs lest than $60 a month to heat in the dead of winter.
Flip to a house, also in NYC, and the heating bill was 4x for 2x more space...I think mostly because it was a detached home with all sides open.
Every house and rental I've encountered so far has given me the monthly heating/cooling cost up-front, which has so far been fairly accurate, assuming you hold at an area-normal temperature indoors. And they've all been able to tell me the R-value of the insulation in the walls and roof or attic. If ever it's more than like $100 for a single-family home, you pretty much know the insulation is bad or terrible.
https://ec.europa.eu/energy/eu-buildings-factsheets-topics-t...