The substance of Senator Rubio's has nothing to do with the solvency of entitlement programs. Rather, he objects to the government rather than private citizens caring for the elderly. His argument is that if people know the government will take care of the elderly they will not, and that therefore the people are weakened because they are ceding to the government their traditional role. I disagree:
1) Social Security greatly reduces senior poverty. That strengthens us as a people. Social Security wasn't implemented arbitrarily-- it was implemented because communities weren't doing enough to care for the elderly.
2) With Social Security now well established, people still believe that it is their job to care for elderly parents. If an elderly parent needs help, no one tells them to call their Social Security office.