In my working days when investment returns were in the 7 to 8% range I remember sitting around a negotiating table when the union folks wanted to change the pension plan from a defined benefit plan to a "money purchase" plan (probably the equivalent of your 401K's where the company and the employee contribute). At that time the pension plan was in surplus due to the decisions made by the investment company managing the plan and therefore the company didn't need to contribute.
The plan was converted and the surplus distributed to the members and there were multiple choices given to the members on where to invest their pots of money. Five years later we found that most of the members invested in GIC's or other lower than inflation vehicles with a few taking a bath on high risk investments. In the end it was a substantial advantage to the company (no risks) and it was a failure for the employees.
Bottom line is that unless people are disciplined and can look after their money for retirement (and only a few seem to be able to do this) they will have only social security to rely on.