The lesson there is you'd better have more going for you than SS!
No reasonable person would argue that having more than SS is a good plan, but many people can't. People at the bottom will not be investing money they aren't forced to pay to SS as wealthier people may. They will be using it to survive. Any good conservative would say that if SS is insufficient in the future, let's get rid of it today. I say let's improve it.
Then lets improve it by making it only mandatory to those below a certain percentage of the poverty line. I dont need it i dont want it with my education im making 40k starting out i dont need it and im intelligent enough that i will invest it and invest it well.