Earlier quoted context omitted.
The economists are worried because (retirement) savings are nothing more than a claim on future labor. As people grow older and are less capable of taking care of themselves other people need to care for them. People can be secure in their retirement when the number they have saved is sufficient to purchase the labor they need later in life. But what will the price of that labor be when birth rates collapse and there…
First, I'd say that if those politicians are so worried, then perhaps they should work on building societies that people actually want to bring children into. Mainly though, I wonder - where is all the extra productivity that has supposedly developed over the last half century or so? Shouldn't that be able to cover over a declining population?
I think we can also make a Moore's law analogy here. As CPUs get faster we write slower code.