They can pay everyone $2000 a month, if a loaf of bread is $2000 if you catch my drift.
The demographic issues are a consequence of political choices, e.g. the way we prevent working age people from coming to this country to pay into the system. (and now, kick some of them out).. but also, the ways that choose not to enable families to comfortably have children.
I don't know what "proof" you have but remember that the economic impacts of demographic shifts are pretty broad, so I would suggest you validate that your source is taking that into account, and isn't intentionally biased for political reasons. The overwhelmingly predominant economic opinion is that immigration is very valuable in growing a country's wealth.
It's got to go. It's a shame people were lied to but the reality is we can't keep things the way they are.