I think you're committing a fallacy here related to demand for transportation.

The goal of building new transportation infrastructure is to provide more transport services and to reduce congestion.

As a matter of fact, there is huge latent demand for transportation services, so when you build new roads etc almost all of the benefit comes as more usage of transportation, and congestion doesn't go down.

But the fallacy you're committing is ignoring the fact that that extra transportation is a benefit. People wanted to take those journeys!

By the way, if you want to reduce or even eliminate congestion, there is a very easy way to do it. Charge for road use. Modern technology makes this feasible!