That makes sense. It seems like during the continuous "building up America" period of the late 40s through mid 70s there was no problem of getting shit done at reasonable cost, because of continuously available institutional knowledge.

Once large infrastructure projects become sporadic in nature, you begin to run into issues.

The solution has to be continuous stimulus, but that also runs into problems of corruption and capture by special interests (the longer the stimulus, the more incentive there is for 3rd parties to appropriate funds).