I think part of it was that it is/was a lot harder for most countries to insulate themselves like Aust & NZ could. How could they manage it effectively without all of Europe shutting down together?
Jazz most /all euro borders were closed except for residents and cross-border workers.
Europe shutdown, and the schengen agreement was put on ice. Not all at once but throughout march. The UK were probs one of the last to do so.
France borders closed 2 months ago, mid March, with security fences and soldiers guarding the local roads that were normally open.
There are still the forest trails to cross into Switzerland if I was inclined to buy something expensive.
The main border crossings were strictly controlled and a passport or work permit needed to cross.
In the first fortnight there were military choppers flying every day or so, plus police patrols. It meant that roads were empty. No PT across the border.
It's all opening up now, similar to oz. The borders will reopen june15
This wouldn't have been as effective as NZ but it wouldve reduced inter-country movement significantly.
So Sweden could do it. And they only needed to control a land border with Norway, plus air and sea.