Most of the cost in infrastructure is actually caused by too many regulations in countries such as the US. It is estimated that current regulations increase the costs by a factor of 6-7.

When you look at Barcelona an how they build there it is obvious that they (currently or at least in the recent past) do not have that problem.

That's also one of the reasons why the Chinese can complete a large infrastructure project like a skyscraper in a few months while we need half a decade for the same task.