Rubber ppm over some threshold safety level is a negative externality worth maybe a few billion in remediation, healthcare costs, etc. (As a society, we're still not convinced pulmonary health as impacted by particulate inhalation is important - which is a mistake. It absolutely is a big deal and negative externality driving a whole host of bad health outcomes.)

Malinvestment into public transit in a way that serves only a limited few of the population and that costs 10x the already high initial estimates is a negative drain on the balance sheet worth 500 billion or more. And this infra is woefully inflexible and static.

California HSR alone is already suboptimal vs. flights, and once we have long distance autonomous self-driving, that'll meet the same demand with 1/100,0000,000th the cost (if you average out the costs and benefits of self driving over all other routes).