Note also that the data was meant for what i assume is the national statistics office. Likely for investigating changes in danish public health over recent years.
Unless by airgapped you mean to build a separate, free standing, network just for delivering medical records to doctor's offices around the nation.
Second, the fact that security is (really!) hard is not a valid argument against doing it.
Third, there's a huge difference between the appropriate levels of security around individual patients' medical histories, a single doctors office worth of patients' data, and then the collective medical histories for every single patient in the nation.
If you buy a cheap knockoff don't complain when it turns out to not be as good.
Hang on: If you're extracting an individual's medical data and putting that on a USB stick you better make sure it's encrypted, and that there are audit trails in place for who extracted the data, when, and why, and where they put it.