People 60 years ago should have known better.

Bastiat was writing about how 'legal plunder' as he describes it, destroys civilizations nearly a century before the new deal era.

People contemporary to the passage of SS knew it was doomed to failure and spoke out against it.

Truth be told SS has failed multiple times since its inception hence the necessity to continually increase the percentage of the levy. That alone is first hand evidence of its insolubility.