* City roads are narrow and don't have empty space just waiting to be painted green. Bike lanes will cost you parking spots or a car travel lane. This gets huge pushback.
* Dangerous drivers must be removed from roads. You can be hit, killed even, with video evidence and the driver may escape punishment entirely.
* Cities (or specifically NIMBY residents) must stop resisting increased density, mixed use, and useless parking minimums. Not everyone wants to live in a suburban development, miles from useful amenities.
* Bikes and alternative transportation are compliments and need to be developed together. Biking to transit hubs is huge. It's not just green paint wherever it fits.