Sweden is more comparable to Germany in population structure. Especially Norway and Finland are completely different.

Have a look here (tone is satirical) for a comparison of Sweden's and Germany's graphs:

https://philip.greenspun.com/blog/2021/11/12/wear-a-mask-and...

Germany's numbers are exploding right now. In the U.S. you could also compare New York and Vermont. New York was more like Sweden (not by choice, but through incompetence and extreme population density). Vermont had the officially recommended policies and was a poster child.

Now the Vermont numbers are exploding, while New York's are not.

There is something to be said for the theory that the highly connected nodes in the social graph (who are often very healthy) all need to be infected in a short period. Then the outbreaks stop (like they have always done with the flu).