We might also want to look at climate differences between locations. Denmark and Netherlands have a rather enjoyable e with regards to biking. Other places less so. The other factors are possibly geography and the pure size of the location.
No, Northern Europe most certainly doesn’t have a climate that promotes bicycling. Denmark and Holland are flat, that is true, but so is LA. But SF is not, neither is Portland really, nor do they have very nice weather, and those cities have more far bikes, so I don’t think it’s mostly about geographical factors.
When bicycling I prefer when it doesn't rain ice cold rain almost everyday from October to March, and when it's not windy every single day (though as a kitesurfer I don't complain about THAT).
It's also not ideal when the sun both rises and sets while you're at work, so you have to bike in the dark everyday for three months. But that's strictly speaking not about climate...
And that's Copenhagen. Stockholm is worse in every possible way, darker, colder (OK, it's not as windy) and few bike lanes. Still, more people bike there than in LA or Miami.
