Every house I know has blinds in Belgium. Are you perhaps talking more modern like Sweden?

I've almost always seen indoor blinds, which are useless in keeping heat outside the windows. In Southern Europe blinds are outdoor and keep solar radiation outside the glass, and there are separate curtains inside for privacy when the blinds are open.

Compare Antwerpen[0] or Brussels[1] with Milan[2] or Crete[3] or Barcelona[4]

[0] https://www.google.com/maps/@51.219842,4.4006387,3a,75y,64.8...

[1] https://www.google.com/maps/@50.8398344,4.3562283,3a,75y,90....

[2] https://www.google.com/maps/@45.4558029,9.1837501,3a,75y,29....

[3] https://www.google.com/maps/@35.3266049,25.1255372,3a,75y,34...

[4] https://www.google.com/maps/@41.3880801,2.1358851,3a,75y,256...

I was talking about indoor blinds, my bad!

Every house I can see in my street has no blinds, here in Antwerp.

Coming from France it seems weird to me, and obviously blinds would come very handy right now, but there are obviously a lot of houses with no blinds in Belgium, I can see them from where I stand.

Unless you're talking about curtains or other things that sit inside the house, which are basically useless against heat.

I was indeed talking about the wrong, sorry! ;-)