What happens when there is no money to give to the people who have no money? That is the moral question. It's fine to say that the old people should have saved more, they should have worked an extra job, they should have done without cable TV, they should have invested more wisely. Saying that doesn't change the fact that there will be old people who do not have money. These old people will believe that they need food and shelter and medical care.
Will they get it? At the arch-plutocrats' end of things, the Koch brothers' end, the end occupied by the most devout worshippers of Ayn Rand, the answer is: no. That's the goal. It's long since time for the sloppy, implicit, badly supported social contract to go away. Rich people have been trimming their contribution to the general revenue for decades now. They are not interested in paying the premium that keeps old people and ailing people or just backward people out of the streets. If the day comes that they have to travel to and from their various compounds in armored helicopters, they can afford the helicopters. It's not their problem.
David Brooks do not believe they are that kind of person. David Brooks are responsible. David Brooks care about the need to "invest" in "effectiveness" for all.
Alas, living is not effective. Employers have stopped paying people for their post-productive years. They have done this, welfare-capitalistically, with the sense that the cost and responsibility they are shedding will be picked up by...someone, somewhere.