I think it's a "build it and they will come" situation.
He mentions Copenhagen in the video, and I can safely say that the majority of cyclists in Copenhagen do not consider themselves part of a specific cycling culture. Of course there are cycling clubs and such, but the average person on a bike is just trying to commute without giving any consideration of whether it's normal in other places.
Copenhagen also has decent public transport, busses, trains, metros, so it's not like people need to ride a bike to get around even without cars.
Copenhagen is very flat geographically and had a high density, so it's fast and easy to get anywhere on a bicycle. Other even smaller cities in Denmark have fewer cyclists, either due to hills or longer distances between points of interest, so while there is a general bicycling culture in Denmark, Copenhagen is something else.
In the second largest city, Aarhus, they recently build a city train hoping to lower the quantity of car commuters, but the result turned out to be that it actually lowered the quantity of bicycle commuters as well. Probably because they have the longest hill bicycle lane in the country. It goes to show that the ease of transport is more important than the culture.
Traffic management is difficult like that. The population moves very fluidly between methods of commuting. When something is build, the users will come.
That's also how Tokyo managed to get rid of the cars in the city. They invested heavily in mass public transport before it was needed and it just works so well. There are very few cars in the world's largest city. There are also very few bicycles though. You could say that Tokyo has a public transport culture, but that obviously didn't exist without public transport. Same with bicycles.
everyday rides helps keep Seattle's bike culture going - I think it's pretty cool.
A big part of bike culture is finding people to ride with. A way people do this is by joining cycling clubs, but not everybody wants to Lycra up to get dropped.
Seattle also has the huge cascade bicycle club, but it can be a bit... stillted.
I love having a catalog of rides in the city. I'd love to see Everyday Rides for many more!
True bike culture is when cycling is normal and not special. I cycle to work and go everywhere on my city on my bike. I don't want a car. To me cycling is normal. It's not a past time. It's my transport.
If a place has extensive and safe cycling infrastructure, cycling can become the easiest way to get around. That's when a bike culture can develop.