By providing free or cheap parking for people that don't live there. Urban land is extremely expensive and parking generally doesn't cost what it should, other land uses would provide a lot more revenue. Parking in US cities is greatly over provisioned to make life easy for suburbanites, destroying urban fabric.
Massive ongoing investment into roads. EV incentives that would pay for 3-4 ebikes outright. Big 3 bailout. Cash for clunkers. Impact fees from developers towards roads. As others said parking requirements. There is so much beyond that too.
> Road wear increases with the fourth power of axle weight iirc
That's not actually true, and the paper that describes the "fourth power" thing even says that right up front.
If you massively oversimplify the model so that you've got all vehicles fitted with infinitely hard bicycle tyres on a perfectly smooth surface, it kind of works out, but not quite.
Interesting! Nevertheless I believe it is true that bike and pedestrian paths are much cheaper to construct and maintain than roads for cars and trucks.