> Build more bike lanes.

The problem is that you may not have the room for it. The US might often have more room to retro-fit bike lanes, due to their roads be generally pretty wide. European cities, like Copenhagen have a massive issue as more and more people get things like cargo bikes and electric bikes. The bike lanes needs to be expanded to accommodate them, but there's no room. You'd have to remove cars from large parts of the city, which sounds great, except you do need to have the option to drive, either due to distances, public transport or deliveries. You can't do parking and have people walk, because there's also no room for parking.

For some cities I also don't see bike lanes as solving to much. Some cities, again often in the US have a huge area and millions of people. Distances in cities like Houston, New York, Los Angeles or Atlanta are just insane, taking up enough space to cover half of a small European nation.