I've been to Copenhagen in the dead of winter with snow on the ground and my mind was blown by how many bikes there were on the streets. It really is an adaptable activity.

I believe they prioritise clearing snow/ice from the cycle lanes.

Personally, I enjoy cycling on snow as it's often not that slippery and due to the cold, I'll usually have a fair amount of clothing to act as padding for if I do come off. Black ice is worse as the rest of the road may be fine, so you go fast until suddenly you're sliding down the road.