The "Not Just Bikes" channel in YouTube makes the awesome observation that building infrastructure for cyclists actually improves driving times for a car drivers, and may be actually cheaper to implement, certainly much cheaper to maintain.

The calculation for car-saturated cities is that each drive takes as long as fastest alternative mode, and no faster. Which kinda makes sense to me - as you build more infra people chose to not drive, making driving a lot more fun for the die-hards and the ones where that's not an option.