Do governments have a responsibility to ensure that their citizens prepare for retirement?
There are arguments on both sides of this issue.
On the one hand, governments do need to ensure that citizens prepare for retirement (through programs such as Social Security) so that social problems will be prevented. Rich countries, in particular, would not want to have older people to be impoverished after retirement simply because they did not plan well. This poverty would be seen as a social problem. It might also end up hurting the economy of the country as senior citizens did not have enough money to be consumers.
On the other hand, people have responsibility for their own choices. They should be free to choose whether they want to save for retirement. They should then bear the responsibility (perhaps along with their families) for taking care of themselves if they choose not to save. From this point of view, the government should not force people to make wise choices or protect them from their own foolishness.
Thus, arguments can be made for both sides.