An excellent question. The "traffic engineer" profession is deeply broken. https://www.nytimes.com/2023/01/06/us/widen-highways-traffic.html
Widening Highways Doesn’t Fix Traffic. So Why Do We Keep Doing It?

With billions of dollars available to improve transportation infrastructure, states have a chance to try new strategies for addressing congestion. But some habits are hard to break.

The New York Times

We now have overwhelming evidence from a million different directions that sprawly car culture *doesn't work*. Suburbs don't pay for themselves. More lanes don't decrease traffic. Stroads kill people & inhibit economic growth. Parking is economic deadweight.

We refuse to learn.

The whole car/sprawl complex has reached such size & momentum that it just thunders on despite all this evidence -- one of many ways the US punches itself in the face over & over again while bragging about exceptionalism.
@drvolts and now it’s to the point where folks defend the way it is because of how far down that path we are …. Basically it’s “too much work to change now” is the defense, along with “this is what Americans want” … “freedom in their own cars” .. very frustrating
@buck @drvolts See the Sunk Cost Fallacy.