I am living in the EU and writing from personal experience. Fad is fad even if it makes it into law. Mineral wool has other disadvantages.

But we digress, I am firmly convinced that such narrow focus on energy efficiency of buildings to the detriment of other things is exactly the "affluent" technological solution the paper is critical about.

I understand that, but also think what makes it a not-fad is that EU does not have a lot of its own energy sources and winters can be hard. So to me it makes sense to try to be as energy efficient as possible and also not send a lot of money to e.g. Russia if it's avoidable. I also understand that constructing low-energy buildings is much harder than the standard ones. But I fully believe that science and engineering, when given such task, can master that, given enough time.

It's not so hard, but EU is so far removed from practice that it can't set up the incentives right. There's a parallel with EU's policy on biomass energy that ended up (partially) driving deforestation here in Slovakia.