> If this bit of context was clear from the get go it would have been a lot easier for those from EUR where we would expect vents outside the apartment to be the norm. ( Not speaking for all EUR, so there may be places this is not the norm )

It is the norm in newer buildings, but there are plenty of older houses or flats blocks in the EU that don’t have a good ventilation system. It’s similarly expensive same in the UK and I cannot say about Norway and Switzerland, but I would think that it is not better in the other non-EU bits of Europe.